Route 322 begins at an intersection with Route 69 in Wolcott and curves east, southeast, and south to the southeast corner of the town, then turns east into Southington. In Southington, it continues east near the Southington-Cheshire town line, intersecting I-84, and then turns southeast, briefly crossing into Cheshire before crossing the Quinnipiac River and reentering southeastern Southington. It continues generally southeast, ending at an interchange with I-691 near the Southington-Meriden town line.
Route 322 was established in 1963, running from Route 69 to then US 6A (Meriden Road) in Wolcott. The year before becoming a signed route, Route 322 was taken over by the state and designated as unsigned SR 522 as part of the Route Reclassification Act. In 1967, with the decommissioning of US 6A, it was extended east along former US 6A to I-84 in Southington. In 1987, with the opening of I-691, the portion from I-84 to Exit 4 of I-691 was transferred from Route 66 (which was truncated to I-91) to Route 322.