The present study was designed to evaluate the quality of black tea available in the markets of Peshawar, Pakistan and to detect adulteration in black tea. Seventeen non branded samples of black tea were analyzed for their quality evaluation. Moisture%, ash%, caffeine%, tannin%, water extract% and added colors were determined. Moisture contents ranged from 2.39 to 10.0%, ash 4.2 to 10.4%, caffeine 0.13 to 3.98%, tannin 0.04 to 6.83% and water extract 9.3 to 39.2% in different samples of black tea. It was found that five samples were of inferior quality due to low caffeine contents than the standard value prescribed by Pakistan Food Laws and Regulations. However, two samples were adulterated with added color. The samples containing less caffeine than standard also exhibited less tannin contents. Rest of all the samples were found fit for human consumption according to the Food Laws and Regulations set by Government of Pakistan.