Pd and Ni contacts on various p-InP substrates which were grown by liquid-encapsulation Czochralski (LEC) and metal organic chemical vapor deposition (MOCVD) were investigated. Pd contacts on the substrates supplied by one manufacturer were found to be ohmic contacts with a minimum contact resistivity of ∼ 5xl0-5Ω-cm2 for annealing temperature between 420°C and 500°C. However, ohmic behavior was not observed for Pd contacts on other substrates. Hall measurement and double-crystal x-ray diffractometer were used to evaluate the substrates. It was speculated that existence of intrinsic defects in p-InP grown by LEC method may be responsible for the observed ohmic behavior. This defect-assisted tunneling mechanism is potentially usefully for making ohmic contacts on other compound semiconductors.