The vicissitudes of Heinz's Bodies in the hematuria, in the blood, and of those produced by Yoshida's method after the experimental renal impairments on rabbits by means of Cantharidin causing damages of renal glomeruli and of uranium nitrate and mercuric chloride causing damages of renal tubules. And the following results were obtained. 1. The formation of Heinz's Bodies was accelated by Cantharidin. 2. The vicissitudes of Heinz's Bodies produced by Yoshida's method were in parallel with toxicity and lassitude after renal impairments. 3. It might be thought that Heinz's Bodies in the urine were formed at first in the blood and then were excreted into the urine. Incidentally, it also might be thought that they were formed in the erythrocytes while which were in the tubules following being filtered from the renal tubules. In the renal tubules were necessitated to be relatively normal condition.