Shimek State Forest is an Iowa state forest maintained by the Iowa Department of Natural Resources.

Its five units are strung along the Des Moines River a few miles above its confluence with the Upper Mississippi River in Lee and Van Buren Counties in the southeast corner of Iowa.

Its 9,148 acres (37 km2) contain one of the largest remaining contiguous forests in the state with large stands of mixed oak-hickory forest with about 1,000 acres (4 km²) of planted pine.

The Keosauqua (918 acres (3.7 km2)) unit is upriver, opposite Keosauqua and adjoins Lacey-Keosauqua State Park and wildlife management areas.

Its earliest development was by the Civilian Conservation Corps on exhausted, abandoned farmland.