An analytical method was developed for determination of valsartan in commercial drug and sewage sludge samples by HPLC-UV using a single wavelength (250nm). The effect of different environmental storage conditions on the stability of valsartan was examined for a period of 85 days, after which no degradation was observed. The post oral administration stability of the valsartan was also investigated by testing valsartan under simulated gastric conditions. Results obtained showed that the structure of valsartan was conserved over 3.5-h period. The calibration plot of the study was linear over a wide concentration range with a correlation coefficient of 0.9999. The limit of detection and limit of quantitation were found to be 0.014 and 0.046 mu gmL(-1), respectively. The percentage recovery of valsartan from sewage sludge was found to be 99.8%.