Illinois Route 10 (IL 10) is an arterial east–west state highway that runs from rural Mason County east to Champaign, a distance of 91.35 miles (147.01 km).

Illinois 10 starts at US 136 about 12 miles east of Havana. The highway heads south to Easton, and then changes direction to reach Mason City and Lincoln. The highway passes through many small towns on the way to Champaign, and it runs through Clinton and by Clinton Lake. The highway closely parallels Interstate 72 for the last 10 miles before reaching US 150 in Champaign.

Illinois 10 has undergone major changes since it was initially established. Originally, SBI Route 10 followed Interstate 72 much more closely and ran from Jacksonville to Danville. Over the years, it has been dropped from Jacksonville, reinstated in Decatur, dropped entirely west of Danville, reapplied and dropped in Havana and then finally reapplied east of I-72. This last revision was made in 1974.

County	Location	mi	km	Destinations	Notes
Mason	​	0.0	0.0	US 136
	Mason City	11.7	18.8	IL 29
Logan	Lincoln	28.5	45.9	I-55 to I-155 north – Bloomington, Springfield, Peoria IL 121 begins	West end of IL 121 overlap; northern terminus of IL 121; I-55 exit 126
		30.2	48.6	I-55 BL (Lincoln Parkway)
		32.3	52.0	IL 121 south (Limit Street)	East end of IL 121 overlap
De Witt	​	51.7	83.2	US 51
	Clinton	52.5	84.5	IL 54 west (Van Buren Street)	West end of IL 54 overlap
		52.9	85.1	US 51 Bus. (Grant Street)
		53.4	85.9	IL 54 east	East end of IL 54 overlap
	Weldon	65.0	104.6	IL 48
Piatt	​	78.9	127.0	I-72 – Decatur, Champaign	I-72 exit 172
Champaign	​	83.4	134.2	IL 47 north	southern terminus of IL 47
	Champaign	91.35	147.01	US 150 (Prospect Avenue, Springfield Avenue)
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus

• Illinois Highway Ends: Illinois Route 10