With the progress of farming and foresting, the demand of agricultural pesticide has been remarkably increased and accordingly, its intoxication has been widely publicized. Among the pesticides, organophosphorus chemicals has been believed to be almost nontoxic because they are not accumulative in the tissue. This study is attempted to examine the effects of DDVP which has been used most frequently on the kidney. And they were divided into normal and experimental groups. The results obtained from this experiment are as follows. 1) BUN, serum creatinine are increased in the group of DDVP administered while serum cholinesterase is suppresed significantly. 2) Microscopically, swelling and degeneration of tubular cells and hyaline casts in tubules. Ultrastructually swelling of mitochondria, partial fragmentation of cristae and electron dense bodies in the kidney are observed in the group of DDVP administered.