FIU opened a seven-point lead early, but WKU erased that quickly as Jackson drilled back-to-back 3-pointers and Price added one from long distance to take a 22-19 lead. FIU never led or tied again.
The Hilltoppers made four more 3s in the half and led 36-28 at the break.
Western Kentucky led by 10 with 8:11 to go, but used a 12-point run - including Chris Harrison-Docks' 3-pointer - to put away FIU for good.
Jackson made five 3-pointers as WKU went 11 of 21 from beyond the arc and shot 58 percent overall.