Losartan potassium is widely produced and marked drug by many Pharmaceutical companies in Bangladesh. The performance evaluation (Namely, some physical parameters, potency, and disintegration and dissolution profile) of Losartan potassium tablets from different pharmaceutical companies was carried out in order to find out whether they really complied the required standards. As a part of evaluation of physical parameters, the size and shape, specially, thickness of representative samples of each pharmaceutical companies as well as their disintegration and dissolution profile were evaluated and they were found to be uniform.