Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Madlin Park | Park | 190 | Cook | 41 49 33 N | 087 51 15 W |
| Madonna della Strada Chapel | Church | 181 | Cook | 41 59 58 N | 087 39 22 W |
| Madonna High School | School | 205 | Kane | 41 45 28 N | 088 18 15 W |
| Madonna High School (historical) | School | 184 | Cook | 41 56 19 N | 087 43 42 W |
| Madonnaville | Populated Place | 223 | Monroe | 38 15 54 N | 090 14 48 W |
| Madonnaville Cemetery | Cemetery | 202 | Monroe | 38 18 42 N | 090 15 24 W |
| Maercker Elementary School | School | 238 | DuPage | 41 46 53 N | 087 58 27 W |
| Maeys | Locale | 123 | Monroe | 38 13 17 N | 090 16 46 W |
| Maeystown | Populated Place | 143 | Monroe | 38 13 29 N | 090 14 00 W |
| Maeystown Creek | Stream | | Monroe | 38 09 09 N | 090 15 00 W |
| Maeystown Historic District | Park | 148 | Monroe | 38 13 30 N | 090 13 57 W |
| Magassi Cemetery | Cemetery | 146 | Fayette | 38 45 27 N | 089 08 46 W |
| Magee School (historical) | School | 208 | Macon | 39 53 48 N | 088 53 34 W |
| Maggie Rogers Park | Park | 255 | Cook | 42 07 10 N | 088 05 48 W |
| Maggot Creek | Stream | | Fayette | 38 46 21 N | 089 12 17 W |
| Magic Carpet Airport | Airport | 274 | Henry | 42 10 17 N | 088 22 00 W |
| Magic Mirror Learning Center | School | 184 | Cook | 41 46 36 N | 087 42 09 W |
| Magil Hall | Building | 243 | McLean | 40 29 32 N | 088 59 29 W |
| Magin Lake | Reservoir | 164 | Madison | 38 39 48 N | 089 56 48 W |
| Magin Lake Dam | Dam | 164 | Madison | 38 39 48 N | 089 56 48 W |
| Magnet | Populated Place | 230 | Coles | 39 26 21 N | 088 23 52 W |
| Magnolia | Populated Place | 202 | Putnam | 41 06 49 N | 089 11 40 W |
| Magnolia Cemetery | Cemetery | 201 | Putnam | 41 06 49 N | 089 11 58 W |
| Magnolia Cemetery | Cemetery | 200 | Putnam | 41 06 48 N | 089 11 59 W |
| Magnolia Corner | Populated Place | 185 | Fayette | 39 05 40 N | 088 51 09 W |
| Magnus Farm | Locale | 212 | Cook | 42 03 53 N | 087 58 25 W |
| Maguire Center | Hospital | 190 | Cook | 41 51 30 N | 087 50 02 W |
| Maguire School (historical) | School | 213 | McDonough | 40 28 20 N | 090 38 17 W |
| Mahalia Jackson School | School | 186 | Cook | 41 44 02 N | 087 38 45 W |
| Maher Hill | Summit | 188 | Gallatin | 37 39 02 N | 088 21 35 W |
| Maher School | School | 182 | Grundy | 41 09 27 N | 088 17 56 W |
| Mahle School (historical) | School | 173 | Bond | 38 57 40 N | 089 19 05 W |
| Mahomet | Populated Place | 223 | Champaign | 40 11 43 N | 088 24 15 W |
| Mahomet Cemetery | Cemetery | 218 | Champaign | 40 11 36 N | 088 24 08 W |
| Mahomet Gas Storage Area | Oilfield | 229 | Champaign | 40 14 33 N | 088 25 17 W |
| Mahomet United Methodist Church | Church | 220 | Champaign | 40 11 39 N | 088 24 18 W |
| Mahomet-Seymour Junior High School | School | 232 | Champaign | 40 11 56 N | 088 24 33 W |
| Mahon Cemetery | Cemetery | 166 | Effingham | 38 58 29 N | 088 42 42 W |
| Mahon School (historical) | School | 174 | Fayette | 38 57 59 N | 088 56 13 W |
| Mahoney Cemetery | Cemetery | 195 | Shelby | 39 28 35 N | 088 43 14 W |
| Mahoney Park | Park | 137 | Saline | 37 48 59 N | 088 26 53 W |
| Mahoney School (historical) | School | 205 | Shelby | 39 28 17 N | 088 43 54 W |
| Mahoning Mine | Mine | 159 | Hardin | 37 31 31 N | 088 11 03 W |
| Mahoning Mines | Mine | 155 | Hardin | 37 31 19 N | 088 11 26 W |
| Maiden Lane Park | Park | 221 | Kane | 42 05 39 N | 088 16 30 W |
| Maiden Lane School (historical) | School | 198 | Tazewell | 40 29 47 N | 089 28 36 W |
| Maids Run | Stream | | Mercer | 41 06 00 N | 090 43 26 W |
| Main - Hamlin Tennis Center | Park | 183 | Cook | 42 02 00 N | 087 43 25 W |
| Main Building | Building | 182 | Cook | 41 50 03 N | 087 37 45 W |
| Main Consolidated Oil and Gas Field | Oilfield | 148 | Crawford | 38 55 15 N | 087 48 50 W |
| Main Ditch | Canal | 146 | Adams | 40 06 34 N | 091 27 10 W |
| Main Ditch | Canal | 100 | Alexander | 37 17 45 N | 089 24 31 W |
| Main Ditch | Canal | 200 | Lee | 41 41 11 N | 089 35 08 W |
| Main Ditch | Canal | 101 | Massac | 37 19 13 N | 088 52 24 W |
| Main Ditch | Canal | 131 | Peoria | 40 28 39 N | 089 51 04 W |
| Main Ditch | Canal | 153 | Tazewell | 40 19 56 N | 089 42 47 W |
| Main Ditch | Canal | 179 | Whiteside | 41 40 54 N | 090 07 52 W |
| Main Ditch North | Canal | 161 | Mercer | 41 17 18 N | 091 01 52 W |
| Main Drainage Ditch | Canal | 196 | Christian | 39 26 47 N | 089 04 39 W |
| Main Lake | Reservoir | 149 | Hamilton | 38 04 24 N | 088 23 30 W |
| Main Lake Dam | Dam | 149 | Hamilton | 38 04 24 N | 088 23 30 W |
| Main Martinton Ditch Number 3 | Canal | 190 | Iroquois | 40 54 27 N | 087 40 57 W |
| Main Park | Park | 231 | Will | 41 29 45 N | 087 51 34 W |
| Main Place Mall Shopping Center | Locale | 219 | Cook | 41 37 52 N | 087 51 03 W |
| Main Post Office | Post Office | 178 | Cook | 41 52 33 N | 087 38 19 W |
| Main Street Baptist Church | Church | 163 | Madison | 38 53 29 N | 090 08 53 W |
| Main Street Elementary School | School | 198 | Shelby | 39 24 26 N | 088 47 45 W |
| Main Street Historic District | Park | 195 | Whiteside | 41 37 50 N | 089 47 09 W |
| Main Street School | School | 205 | DuPage | 41 47 56 N | 088 04 26 W |
| Main Street School | School | 237 | DuPage | 41 52 15 N | 088 04 04 W |
| Main Street United Methodist Church | Church | 168 | Madison | 38 53 57 N | 090 08 54 W |
| Main Union Special Ditch | Canal | 184 | Henry | 41 33 40 N | 089 57 05 W |
| Maine Park | Park | 190 | Cook | 42 00 58 N | 087 51 31 W |
| Maine South High School | School | 194 | Cook | 42 00 03 N | 087 51 10 W |
| Maine Township High School | School | 195 | Cook | 42 02 17 N | 087 51 28 W |
| Maine Township Jewish Congregation | Church | 196 | Cook | 42 02 38 N | 087 50 46 W |
| Maine Township Town Hall | Building | 195 | Cook | 42 02 38 N | 087 50 55 W |
| Maine West High School | School | 199 | Cook | 42 01 16 N | 087 54 24 W |
| Maizetown | Populated Place | 208 | Vermilion | 39 57 15 N | 087 48 16 W |
| Majewski Metro Park | Park | 198 | Cook | 42 01 04 N | 087 55 38 W |
| Major School (historical) | School | 139 | White | 38 11 20 N | 088 11 54 W |
| Majorville Cemetery | Cemetery | 208 | Hancock | 40 27 35 N | 090 56 40 W |
| Majorville Church | Church | 207 | Hancock | 40 27 35 N | 090 56 43 W |
| Makanda | Populated Place | 136 | Jackson | 37 37 03 N | 089 12 32 W |
| Makanda Cemetery | Cemetery | 192 | Jackson | 37 36 56 N | 089 12 17 W |
| Malan Junior High School | School | 116 | Saline | 37 44 11 N | 088 32 35 W |
| Malcom X College | School | 179 | Cook | 41 52 37 N | 087 40 27 W |
| Malden | Populated Place | 215 | Bureau | 41 25 28 N | 089 22 09 W |
| Malden Cemetery | Cemetery | 217 | Bureau | 41 25 39 N | 089 22 29 W |
| Malden Grade School | School | 214 | Bureau | 41 25 37 N | 089 21 54 W |
| Maley School (historical) | School | 214 | Champaign | 39 57 10 N | 088 17 35 W |
| Malin School (historical) | School | 196 | Christian | 39 23 10 N | 089 02 41 W |
| Mallard | Locale | 161 | Hancock | 40 15 04 N | 091 25 04 W |
| Mallard Bay | Bay | 147 | La Salle | 41 19 13 N | 088 42 01 W |
| Mallard Creek | Stream | | Massac | 37 11 04 N | 088 36 35 W |
| Mallard Creek Shopping Center | Locale | 239 | Lake | 42 22 50 N | 088 03 56 W |
| Mallard Lake County Forest Preserve | Forest | 233 | DuPage | 41 57 59 N | 088 07 56 W |
| Mallard Lake County Forest Preserve | Park | 241 | DuPage | 41 57 25 N | 088 07 28 W |
| Mallard Lake North | Populated Place | 242 | Kane | 41 58 00 N | 088 22 15 W |
| Mallard Lake South | Populated Place | 241 | Kane | 41 57 32 N | 088 22 16 W |
| Mallard Park | Park | 234 | Cook | 42 05 50 N | 088 04 22 W |
| Mallard Pond | Lake | 282 | Lee | 41 38 53 N | 089 17 51 W |
| Mallard Pond | Reservoir | 213 | Cook | 41 42 19 N | 087 52 57 W |
| Mallory Cemetery | Cemetery | 217 | Piatt | 40 08 06 N | 088 27 53 W |
| Mallory Cemetery | Cemetery | 174 | Sangamon | 39 49 58 N | 089 30 31 W |
| Malone Church (historical) | Church | 158 | Tazewell | 40 21 44 N | 089 41 38 W |
| Malone Landing Strip | Airport | 219 | Knox | 40 48 45 N | 090 26 25 W |
| Malone School (historical) | School | 161 | Tazewell | 40 22 41 N | 089 38 31 W |
| Malone Townhall | Building | 164 | Tazewell | 40 21 49 N | 089 39 37 W |
| Maloney Farm Preserve | Park | 186 | Cook | 42 05 19 N | 087 42 13 W |