This chapter describes transplant pathology. Types of transplant pathology are protocol liver biopsy and indicated liver biopsy. Protocol liver biopsy is done according to guidelines rather than in response to the patient’s clinical status. It includes early and late biopsies. Early protocol biopsy is usually performed 7 days after transplantation because liver function tests are insufficient for the diagnosis and assessment of severity of rejection. Late protocol biopsies are performed after 6 months of transplant. This chapter covers the spectrum of diseases seen in post-transplant liver biopsies, differentials as per timing of biopsy, liver transplant rejection, recurrence of primary diseases, post-transplant lymphoproliferative disorder, opportunistic infections, vascular complications, biliary tract complication, and plasma cell hepatitis.