A study was undertaken in 54 renal allograft recipients to evaluate the multiple factors contributing to the pathogenesis of hyperlipidemia after renal transplantation. Serum triglyceride concentrations were found to correlate positively with the cummulative prednisolone dose, and with abdominal skin fold thickness. Serum cholesterol concentrations correlated significantly with serum creatinine concentrations. Patients on beta adrenergic blocking agents had lower plasma free fatty acid concentrations and patients on diuretics had higher serum triglyceride concentrations. The implication of these findings are discussed.