Clinically bladder tumors can be easily diagnosed on cystoscopic examination and biopsy in the pateints withsilent hematuria, teminal dribbling and sysuria. But for the evaluation of the extent of tumor invasion, theauthor performed both barium-air double contrast and triple-fractionated cystogrpahy on 16 patients suspected tobe bladder tumor on cystoscopic examinatin in the radiologica department of B.N.U.H. from Sept. 1982 to Aug. 1983.The obtaned results were summarized as follows. 1. On barium-air double contrast cystography andtriple-fractinated cytography, 13 cases were concluded as bladder tumor, and 3 cases were consistent with thefindigs of chronic inflammation out of the total 16 cases. 2. After operation of 15 cases, 12 cases were confirmedpathologically as transitional cell carcinoma, 1 case as prostatic hypertrophy, and 2 cases as chronicinflammation. Remaining one was biopsied on cystoscopic examination,and confirmed as chronic inflammation. 3.Among 9 cases of transitional cell caracinoma having the evidence of muscle invasion on triplefractionatedcystography, 8 cases were confirmed as more than stage B1 on pathologic study, and the other as chronicinflammation. 4. In detecting multiplicity, presence of ulceration, and evaluation of nature of tumor surface,bariumair double contrast cystography was more excellent than cystoscopic results. 5. Cases presenting bothulceration and cauliflower appearance on barium-air double contrast cystography was more than garade III onmicroscopic evaluation. 6. In conclusion, the author considers the barium-air double contrast andtriple-fractionated cystography are easy to performe, resonable in price and have relatively high accuracy intumor detection, staging and grading.