Hot carrier reliability in submicron PMOSFETs has been investigated. It has been found that in submicron p-channel transistors the punchthrough voltage is seriously reduced due to Hot Electron Induced Punchthrough (HEIP). HEIP effect results from the effective channel length reduction due to hot electron injection into the gate oxide near the drain. Such hot electron injection is most significant at a low stress gate voltage, since hot electrons generated by impact ionization are then easily emitted into the gate oxide. Worst case analysis of the experimental data shows short device lifetime ( less than 1 day) for 0. 8 mu m gate length PMOSFETs due to the HEIP effect.