Objective To investigate the relationship between the renal allograft weight,the body surface area of the host and the allograft function in the first week after transplantation. Methods The correlation of the renal allograft weight, the body surface area of the host and the mean sCr 2~7 days after transplantation was studied in 53 patients. Results Allograft weight has no obvious impact on the mean sCr in the 2~7 days after transplantation( P 0.05). The body surface area of recipients was positively correlated and the ratio of allograft weight to body surface area negatively correlated with the mean sCr in the 2~7 days after transplantation( P 0.01). Conclusions Body surface area of the recipients and the ratio of allograft weight to body surface area are important markers of the allografts function in the first week after transplantation. It is suggested that the recipients with big surface area should be transplanted with allografts of higher weight.