Semiconductor heterojunctions of MOCVD grown InP were fabricated on n-InSb to study some features of a current transport in strained heterojunctions. The MOCVD grown undoped InP samples on InP substrates were characterized by XRD and Hall measurements whereas the InP/InSb heterojunction was characterized by XRD, TEM and I-V measurements in the temperature range 160-305 K. On increasing the voltage, first the current through the heterojunction is found to increase linearly and then it gets saturate due to surface states saturation. When the misfit dislocation density was increased, overlapping in the depletion regions gave rise to a barrier to the current flow there by saturating the current. (C) 2009 Elsevier B.V. All rights reserved.