This study presents the results of the effects of temperature variation on the compressive strength of Grade 40 concrete. The compressive strength was determined on cubes of 150 x 150 x 150 mm. A total of thirty cube specimens were cast, cured in water at ambient laboratory temperature and subjected to different temperature regimes before testing. A concrete mix ratio of 1:1:3 (cement: sand: granite) with water cement ratio of 0.44 was designed for this investigation. Specimens cured for 7 and 28 days were subjected to uniaxial compressive loading tests at room and elevated temperature of 100oc, 150oc, 200oc, 250oc and 300oc for 1 hour duration. The results of this investigation indicated 14.49%, 25.51%, 35.51% and 43.88% decrease in compressive strength at 100oc, 150oc, 200oc and 250oc respectively. Temperature increase of 300oc showed a 53.47% peak decrease in compressive strength.