Influences of the chemotherapy on tumor have been appraised by clinical and pathological points, but in these observation there have been attended with many difficulties. Then cytological changes followed by the chemotherapy were observed. But exfoliative cells in urine also received many physical changes additionally. Then as material I adopted the normal saline solution that poured into bladder in stead of the urine. After the preliminary experiments, and the exfoliative cells were stained by Papanicolaou's method. Carzinophilin, Thio-Tepa and Mitomycin C were used for this studies, and these were administrated intravenously, intramuscularly and topically, respectively. The following results were obtained. The vacuolisation, faintly staining and the destruction of cytoplasma or nucleus, the non-transparency and the transformation of cytoplasma were observed after chemotherapeutic treatment, but the vacuolisation of cytoplasma and nucleus were the most conspicuous and significant. Each drugs influenced to the cancer cells in any degree, but any drugs were more effective by the topical administration to the bladder tumors.Bladder tumor was easily observed cytoscopically, and the biopsy of it was able to repeat as occasion demand. Then we could easily tried the clinical, pathological and exfoliative studies of the bladder tumors under the influence of the chemotherapy.