Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Jehovahs Witnesses South Unit | Church | 184 | Cook | 41 45 02 N | 087 39 36 W |
| Jehovahs Witnesses Stony Island Congregation | Church | 181 | Cook | 41 46 29 N | 087 35 27 W |
| Jeisyville | Populated Place | 177 | Christian | 39 34 38 N | 089 24 18 W |
| Jelkes Creek | Stream | | Kane | 42 05 01 N | 088 16 49 W |
| Jenifer Creek | Stream | | Hancock | 40 14 52 N | 091 25 09 W |
| Jenkins | Populated Place | 224 | De Witt | 40 09 10 N | 089 02 01 W |
| Jenkins | Populated Place | 139 | Williamson | 37 51 15 N | 088 55 39 W |
| Jenkins Cemetery | Cemetery | 140 | Clay | 38 44 13 N | 088 29 05 W |
| Jenkins Cemetery | Cemetery | 136 | Johnson | 37 28 08 N | 088 59 18 W |
| Jenkins Cemetery (historical) | Cemetery | 139 | Perry | 38 00 07 N | 089 31 51 W |
| Jenkins Creek | Stream | | Adams | 40 06 34 N | 091 23 42 W |
| Jenkins School | School | 155 | Jackson | 37 43 40 N | 089 19 27 W |
| Jenkins School (historical) | School | 138 | Clay | 38 44 04 N | 088 29 24 W |
| Jenkins School (historical) | School | 128 | Perry | 37 58 59 N | 089 28 46 W |
| Jenkins-Green Cemetery | Cemetery | 209 | Bureau | 41 20 19 N | 089 27 38 W |
| Jenks Hall | Building | 212 | Kane | 41 45 18 N | 088 20 56 W |
| Jenner Elementary School | School | 178 | Cook | 41 54 02 N | 087 38 25 W |
| Jennie Huizenga Memorial Library | Building | 189 | Cook | 41 40 06 N | 087 47 03 W |
| Jennifer Creek Reservoir | Reservoir | 164 | Hancock | 40 14 54 N | 091 24 55 W |
| Jennifer Creek Reservoir Dam | Dam | 164 | Hancock | 40 14 54 N | 091 24 55 W |
| Jennings Farm Cemetery | Cemetery | 161 | Jefferson | 38 24 48 N | 088 56 48 W |
| Jennings Park | Park | 200 | Cook | 42 05 51 N | 087 50 09 W |
| Jennings Spring | Spring | 186 | Pike | 39 40 07 N | 091 05 06 W |
| Jenny Lind Chapel | Church | 239 | Henry | 41 17 29 N | 090 17 56 W |
| Jenny Ridge Cemetery | Cemetery | 129 | Saline | 37 38 20 N | 088 41 27 W |
| Jensen Park | Park | 248 | Cook | 41 59 53 N | 088 08 46 W |
| Jensen Park | Park | 182 | Cook | 41 57 55 N | 087 43 15 W |
| Jensen Scholastic Academy | School | 182 | Cook | 41 52 26 N | 087 42 05 W |
| Jensen Woods Camp | Locale | 214 | Brown | 40 03 37 N | 090 51 30 W |
| Jenson Park | Park | 219 | Cook | 41 59 51 N | 088 03 07 W |
| Jenson Park South | Park | 217 | Cook | 41 59 36 N | 088 03 01 W |
| Jeps Hole | Bay | 137 | Cass | 40 03 34 N | 090 10 29 W |
| Jericho Cemetery | Cemetery | 217 | Kane | 41 43 23 N | 088 28 15 W |
| Jericho Lake Diversion | Channel | | Kane | 41 43 59 N | 088 22 33 W |
| Jericho Lake Park | Park | 204 | Kane | 41 44 17 N | 088 23 12 W |
| Jericho School (historical) | School | 169 | Greene | 39 24 16 N | 090 16 21 W |
| Jerling Junior High School | School | 211 | Cook | 41 36 57 N | 087 50 08 W |
| Jerome | Populated Place | 183 | Sangamon | 39 46 03 N | 089 40 50 W |
| Jerome Cemetery | Cemetery | 288 | McHenry | 42 24 25 N | 088 35 54 W |
| Jerome Elementary School | School | 127 | St. Clair | 38 33 42 N | 090 09 10 W |
| Jerry E Staab Airport | Airport | 171 | Woodford | 40 47 37 N | 089 30 26 W |
| Jerry Slough | Stream | | White | 38 06 51 N | 088 00 10 W |
| Jersey Cemetery | Cemetery | 226 | Champaign | 40 14 42 N | 088 18 26 W |
| Jersey College School (historical) | School | 183 | Morgan | 39 50 02 N | 090 16 37 W |
| Jersey Community High School | School | 192 | Jersey | 39 07 32 N | 090 19 49 W |
| Jersey Community Hospital | Hospital | 190 | Jersey | 39 06 38 N | 090 20 34 W |
| Jersey Community Hospital Heliport | Airport | 192 | Jersey | 39 06 40 N | 090 20 33 W |
| Jersey Community Hospital Heliport | Airport | 190 | Jersey | 39 06 36 N | 090 20 37 W |
| Jersey County | Civil | 178 | Jersey | 39 04 00 N | 090 21 00 W |
| Jersey County Courthouse | Building | 202 | Jersey | 39 07 08 N | 090 19 45 W |
| Jersey County Farm (historical) | Locale | 192 | Jersey | 39 08 30 N | 090 26 21 W |
| Jerseyville | Populated Place | 201 | Jersey | 39 07 12 N | 090 19 42 W |
| Jerseyville Aviation Inc Airport | Airport | 183 | Jersey | 39 05 39 N | 090 18 48 W |
| Jerseyville Church of Christ | Church | 178 | Jersey | 39 08 14 N | 090 20 23 W |
| Jerseyville Downtown Historic District | Park | 201 | Jersey | 39 07 10 N | 090 19 39 W |
| Jerseyville East Elementary School | School | 196 | Jersey | 39 07 20 N | 090 19 27 W |
| Jerseyville Hollow | Valley | | Jersey | 38 58 06 N | 090 26 05 W |
| Jerseyville Municipal Building | Building | 200 | Jersey | 39 07 08 N | 090 19 31 W |
| Jerseyville Post Office | Post Office | 201 | Jersey | 39 07 11 N | 090 19 43 W |
| Jerseyville Public Library | Building | 201 | Jersey | 39 07 06 N | 090 19 49 W |
| Jerseyville West Elementary School | School | 196 | Jersey | 39 06 54 N | 090 20 24 W |
| Jerusalem Baptist Church | Church | 181 | Cook | 41 49 05 N | 087 37 52 W |
| Jerusalem Church | Church | 220 | Jackson | 37 36 50 N | 089 22 14 W |
| Jerusalem Deliverance Temple | Church | 180 | Cook | 41 46 36 N | 087 35 56 W |
| Jerusalem Evangelical Lutheran Church | Church | 191 | Cook | 42 02 18 N | 087 46 56 W |
| Jerusalem Lutheran Church | Church | 166 | Madison | 38 39 53 N | 089 59 55 W |
| Jerusalem Missionary Baptist Church | Church | 249 | Winnebago | 42 16 30 N | 089 08 01 W |
| Jerusalem School (historical) | School | 195 | Montgomery | 39 07 08 N | 089 20 08 W |
| Jerusalem United Methodist Church | Church | 204 | McDonough | 40 31 25 N | 090 35 54 W |
| Jerusalem University College | School | 246 | Winnebago | 42 15 52 N | 089 01 55 W |
| Jesk Park | Park | 211 | Cook | 41 36 33 N | 087 46 35 W |
| Jesla School | School | 181 | Cook | 41 46 25 N | 087 35 39 W |
| Jess | Populated Place | 186 | Sangamon | 39 45 53 N | 089 40 03 W |
| Jesse Creek | Stream | | Richland | 38 47 08 N | 088 13 38 W |
| Jesse Owens Community Academy | School | 184 | Cook | 41 40 03 N | 087 37 21 W |
| Jessee Cemetery | Cemetery | 201 | Champaign | 39 53 37 N | 088 11 50 W |
| Jessie 'Ma' Houston Playlot Park | Park | 181 | Cook | 41 48 13 N | 087 36 19 W |
| Jesuit House | Building | 180 | Cook | 41 47 37 N | 087 35 49 W |
| Jesus Christ Mission | Church | 187 | Cook | 41 53 15 N | 087 45 30 W |
| Jesus is the Answer Missionary Baptist Church | Church | 181 | Cook | 41 58 05 N | 087 39 18 W |
| Jesus Name Apostolic Pentecostal Church | Church | 147 | Tazewell | 40 40 10 N | 089 33 40 W |
| Jesus the House of Prayer of the Lord Jesus Christ | Church | 180 | Cook | 41 40 30 N | 087 37 06 W |
| Jett Number Cemetery | Cemetery | 179 | Bond | 38 59 28 N | 089 25 52 W |
| Jew Lake | Swamp | 116 | St. Clair | 38 24 19 N | 089 43 16 W |
| Jewel Mine Number 2 | Mine | 139 | Perry | 38 00 25 N | 089 16 08 W |
| Jewelers Building | Building | 183 | Cook | 41 52 54 N | 087 37 33 W |
| Jewell Hall | Building | 189 | Macoupin | 39 17 21 N | 089 52 20 W |
| Jewell Road | Populated Place | 235 | DuPage | 41 52 36 N | 088 08 09 W |
| Jewett | Populated Place | 178 | Cumberland | 39 12 28 N | 088 14 45 W |
| Jewett Cemetery | Cemetery | 173 | Cumberland | 39 12 17 N | 088 15 36 W |
| Jewett Community Church | Church | 177 | Cumberland | 39 12 36 N | 088 14 38 W |
| Jewett Park | Park | 206 | Lake | 42 10 09 N | 087 50 56 W |
| Jewett Park Community Center | Building | 206 | Lake | 42 10 11 N | 087 50 57 W |
| Jewett Post Office | Post Office | 177 | Cumberland | 39 12 30 N | 088 14 47 W |
| Jewish Cemetery | Cemetery | 254 | McLean | 40 27 27 N | 089 00 18 W |
| Jewish School | School | 187 | Cook | 42 00 39 N | 087 45 29 W |
| Jewitt Cemetery | Cemetery | 181 | Scott | 39 32 10 N | 090 27 15 W |
| JFH Educational Development Center | School | 197 | Cook | 41 57 10 N | 087 49 09 W |
| Jim and Peg RLA Airport | Airport | 197 | Livingston | 41 03 17 N | 088 23 14 W |
| Jim Branch | Stream | | Alexander | 37 13 24 N | 089 19 06 W |
| Jim Young Chute | Stream | | Pike | 39 37 36 N | 091 13 37 W |
| Jim Young Island | Island | 138 | Pike | 39 37 12 N | 091 13 13 W |
| Jimmy Creek | Stream | | Rock Island | 41 27 04 N | 090 35 22 W |
| Jims Creek | Stream | | Marion | 38 42 52 N | 089 02 21 W |
| Jims Hill | Summit | 199 | Union | 37 31 40 N | 089 02 41 W |
| Jims Pond | Lake | 119 | St. Clair | 38 25 40 N | 089 43 03 W |
| Jimtown | Populated Place | 208 | Champaign | 39 54 06 N | 088 21 49 W |
| Jimtown | Populated Place | 170 | Fayette | 38 59 16 N | 089 12 45 W |
| Jimtown Branch | Stream | | Pike | 39 31 20 N | 091 00 53 W |
| Jimtown School (historical) | School | 185 | Rock Island | 41 25 02 N | 090 58 50 W |