Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Morgan Lower Range | Channel | 3 | Multnomah | 45 41 05 N | 122 46 33 W |
| Morgan Turn | Bend | 3 | Multnomah | 45 41 39 N | 122 46 26 W |
| Morgan Upper Range | Channel | 3 | Multnomah | 45 39 59 N | 122 46 12 W |
| Morgan Upper Range | Channel | 3 | Multnomah | 45 39 56 N | 122 46 07 W |
| Morningside Hospital (historical) | Hospital | 79 | Multnomah | 45 30 57 N | 122 33 33 W |
| Morrison Bridge | Bridge | 3 | Multnomah | 45 31 03 N | 122 40 08 W |
| Mount Calvary Cemetery | Cemetery | 300 | Multnomah | 45 31 11 N | 122 44 10 W |
| Mount Hood College Reservoir | Reservoir | 99 | Multnomah | 45 30 49 N | 122 23 49 W |
| Mount Hood Community College | School | 97 | Multnomah | 45 30 59 N | 122 23 44 W |
| Mount Scott City Park | Park | 72 | Multnomah | 45 28 53 N | 122 35 13 W |
| Mount Scott Community Center | Building | 72 | Multnomah | 45 28 58 N | 122 35 20 W |
| Mount Sylvania | Summit | 292 | Multnomah | 45 26 18 N | 122 43 16 W |
| Mount Tabor | Summit | 192 | Multnomah | 45 30 46 N | 122 35 33 W |
| Mount Tabor Annex | School | 87 | Multnomah | 45 31 08 N | 122 36 08 W |
| Mount Tabor City Park | Park | 160 | Multnomah | 45 30 41 N | 122 35 38 W |
| Mount Tabor Hospital | Hospital | 73 | Multnomah | 45 30 18 N | 122 35 19 W |
| Mount Tabor Post Office (historical) | Post Office | 88 | Multnomah | 45 31 08 N | 122 36 07 W |
| Mount Tabor School | School | 71 | Multnomah | 45 31 16 N | 122 36 13 W |
| Mount Talapus | Summit | 1180 | Multnomah | 45 33 43 N | 121 58 03 W |
| Mountain View Cemetery | Cemetery | 218 | Multnomah | 45 31 07 N | 122 17 51 W |
| Mountain View Cemetery | Cemetery | 99 | Multnomah | 45 31 09 N | 122 23 39 W |
| Mouse Island Lake (historical) | Lake | 4 | Multnomah | 45 43 04 N | 122 50 19 W |
| Mouth of Willamette Post Office (historical) | Post Office | 9 | Multnomah | 45 37 19 N | 122 47 49 W |
| Mud Slough | Gut | 5 | Multnomah | 45 36 04 N | 122 41 45 W |
| Mud Slough | Gut | 4 | Multnomah | 45 41 00 N | 122 49 21 W |
| Mulbox (historical) | Locale | 19 | Multnomah | 45 29 22 N | 122 40 24 W |
| Multnomah | Populated Place | 154 | Multnomah | 45 28 10 N | 122 42 26 W |
| Multnomah Arts Center | Building | 151 | Multnomah | 45 28 05 N | 122 42 36 W |
| Multnomah Bible College and Biblical Seminary | School | 76 | Multnomah | 45 31 34 N | 122 34 40 W |
| Multnomah Channel | Channel | 3 | Multnomah | 45 41 39 N | 122 52 07 W |
| Multnomah Channel County Park | Park | 6 | Multnomah | 45 37 31 N | 122 48 39 W |
| Multnomah College (historical) | School | 35 | Multnomah | 45 31 04 N | 122 41 01 W |
| Multnomah County | Civil | 105 | Multnomah | 45 30 00 N | 122 25 04 W |
| Multnomah County Courthouse | Building | 19 | Multnomah | 45 30 59 N | 122 40 41 W |
| Multnomah County Farm and Home (historical) | Locale | 40 | Multnomah | 45 32 14 N | 122 24 24 W |
| Multnomah Creek | Stream | | Multnomah | 45 34 39 N | 122 07 14 W |
| Multnomah Falls | Falls | 198 | Multnomah | 45 34 33 N | 122 06 55 W |
| Multnomah Falls (historical) | Locale | 13 | Multnomah | 45 34 41 N | 122 07 05 W |
| Multnomah Falls Bar | Bar | 6 | Multnomah | 45 34 59 N | 122 07 24 W |
| Multnomah Falls Bar Range | Channel | 6 | Multnomah | 45 34 53 N | 122 07 07 W |
| Multnomah Falls Recreation Site | Locale | 32 | Multnomah | 45 34 37 N | 122 07 00 W |
| Multnomah Falls Upper Range | Channel | 6 | Multnomah | 45 36 04 N | 122 04 19 W |
| Multnomah Park Cemetery | Cemetery | 71 | Multnomah | 45 29 19 N | 122 34 49 W |
| Multnomah Post Office | Post Office | 154 | Multnomah | 45 28 10 N | 122 42 26 W |
| Multnomah School | School | 148 | Multnomah | 45 28 05 N | 122 42 32 W |
| Munra Point | Summit | 553 | Multnomah | 45 37 21 N | 121 57 39 W |
| Navy 10102 Post Office (historical) | Post Office | 11 | Multnomah | 45 33 30 N | 122 42 19 W |
| Nesmith Point | Summit | 1176 | Multnomah | 45 35 16 N | 122 00 26 W |
| Nesmith Point Trail | Trail | 953 | Multnomah | 45 35 32 N | 121 59 49 W |
| Normandale City Park | Park | 66 | Multnomah | 45 31 53 N | 122 36 22 W |
| North Catholic High School | School | 45 | Multnomah | 45 34 39 N | 122 41 54 W |
| North Fork Beaver Creek | Stream | | Multnomah | 45 29 44 N | 122 21 59 W |
| North Fork Bull Run River | Stream | | Multnomah | 45 29 38 N | 122 02 06 W |
| North Fork Dam | Dam | 918 | Multnomah | 45 33 05 N | 122 00 22 W |
| North Fork Gordon Creek | Stream | | Multnomah | 45 30 19 N | 122 06 04 W |
| North Fork Johnston Creek | Stream | | Multnomah | 45 27 59 N | 122 23 49 W |
| North Gresham Park | Park | 100 | Multnomah | 45 30 53 N | 122 26 25 W |
| North Gresham School | School | 99 | Multnomah | 45 30 56 N | 122 26 24 W |
| North Park Blocks | Park | 13 | Multnomah | 45 31 28 N | 122 40 43 W |
| North Portland | Populated Place | 5 | Multnomah | 45 36 37 N | 122 42 12 W |
| North Portland Harbor | Channel | 3 | Multnomah | 45 36 55 N | 122 42 05 W |
| North Portland Junction | Locale | 7 | Multnomah | 45 36 29 N | 122 42 33 W |
| North Portland Post Office (historical) | Post Office | 5 | Multnomah | 45 36 37 N | 122 42 12 W |
| North Powellhurst City Park | Park | 91 | Multnomah | 45 30 51 N | 122 31 24 W |
| North Powellhurst School | School | 89 | Multnomah | 45 30 47 N | 122 31 24 W |
| North Rockwood Park | Park | 80 | Multnomah | 45 31 27 N | 122 29 04 W |
| North Rockwood School | School | 81 | Multnomah | 45 31 30 N | 122 29 08 W |
| Northgate City Park | Park | 32 | Multnomah | 45 35 25 N | 122 43 37 W |
| Northwestern School of Law | School | 127 | Multnomah | 45 27 09 N | 122 40 39 W |
| O'Bryant Square | Park | 18 | Multnomah | 45 31 16 N | 122 40 51 W |
| Oak Ridge | Ridge | 7 | Multnomah | 45 39 16 N | 122 48 05 W |
| Oaks Bottom Wildlife Refuge | Park | 8 | Multnomah | 45 28 13 N | 122 39 34 W |
| Oaks-Pioneer Church Park | Building | 26 | Multnomah | 45 27 54 N | 122 39 40 W |
| Ockley Green School | School | 60 | Multnomah | 45 34 00 N | 122 40 47 W |
| Omaha Parkway | Park | 59 | Multnomah | 45 34 05 N | 122 41 28 W |
| Oneonta (historical) | Locale | 14 | Multnomah | 45 35 15 N | 122 05 06 W |
| Oneonta Creek | Stream | | Multnomah | 45 35 33 N | 122 04 40 W |
| Oneonta Falls | Falls | 140 | Multnomah | 45 34 55 N | 122 04 24 W |
| Oneonta Gorge | Valley | | Multnomah | 45 35 22 N | 122 04 31 W |
| Oneonta Gorge Botanical Area | Area | 195 | Multnomah | 45 35 01 N | 122 04 28 W |
| Oneonta Post Office (historical) | Post Office | 14 | Multnomah | 45 35 15 N | 122 05 06 W |
| Onion Rock | Bar | 6 | Multnomah | 45 32 32 N | 122 16 08 W |
| Oregon Health Sciences University | School | 162 | Multnomah | 45 30 02 N | 122 41 07 W |
| Oregon Health Sciences University Heliport | Airport | 166 | Multnomah | 45 29 44 N | 122 41 14 W |
| Oregon Health Sciences University School of Dentistry | School | 95 | Multnomah | 45 29 55 N | 122 40 59 W |
| Oregon Historical Society Museum and Research Library | Building | 35 | Multnomah | 45 30 57 N | 122 40 57 W |
| Oregon Museum of Science and Industry | Building | 8 | Multnomah | 45 30 30 N | 122 39 59 W |
| Oregon Park | Park | 46 | Multnomah | 45 31 37 N | 122 38 10 W |
| Oregon Yacht Club | Locale | 4 | Multnomah | 45 28 27 N | 122 39 43 W |
| Oregon Zoo | Park | 192 | Multnomah | 45 30 31 N | 122 42 47 W |
| Orient | Populated Place | 169 | Multnomah | 45 28 02 N | 122 21 09 W |
| Orient Post Office (historical) | Post Office | 169 | Multnomah | 45 28 02 N | 122 21 09 W |
| Orwood Spur (historical) | Locale | 18 | Multnomah | 45 35 13 N | 122 46 21 W |
| Osborn Creek | Stream | | Multnomah | 45 32 24 N | 122 26 49 W |
| Osburn Dam | Dam | 266 | Multnomah | 45 28 53 N | 122 14 58 W |
| Osburn Field | Airport | 298 | Multnomah | 45 29 09 N | 122 14 04 W |
| Osburn Reservoir | Reservoir | 266 | Multnomah | 45 28 53 N | 122 14 58 W |
| Our Lady of Sorrows School | School | 76 | Multnomah | 45 28 46 N | 122 36 26 W |
| Overlook City Park | Park | 48 | Multnomah | 45 32 54 N | 122 40 55 W |
| Overlook Triangle | Locale | 56 | Multnomah | 45 33 06 N | 122 41 08 W |
| Oxbow Regional Park | Park | 43 | Multnomah | 45 29 42 N | 122 17 17 W |
| Page Post Office (historical) | Post Office | 161 | Multnomah | 45 31 03 N | 122 16 45 W |
| Paget Creek | Stream | | Multnomah | 45 26 11 N | 122 40 44 W |
| Palatine Hill | Ridge | 160 | Multnomah | 45 26 47 N | 122 40 16 W |
| Palestine Post Office (historical) | Post Office | 47 | Multnomah | 45 30 17 N | 122 37 20 W |
| Palmer (historical) | Locale | 691 | Multnomah | 45 31 14 N | 122 07 44 W |
| Palmer Lake | Lake | 970 | Multnomah | 45 33 59 N | 121 59 46 W |
| Palmer Peak | Summit | 1187 | Multnomah | 45 34 16 N | 122 00 25 W |
| Palmer Post Office (historical) | Post Office | 691 | Multnomah | 45 31 14 N | 122 07 44 W |
| Park Cleone City Park | Park | 40 | Multnomah | 45 32 17 N | 122 26 40 W |