The proximate and mineral composition of four cultivars of Pleurotus mushrooms were tested in order to assess their role in human nutrition. It was found that mushrooms can serve as a good source of protein, dietary fiber and mineral matter. The protein content of mushrooms was much higher than cereals (wheat and maize), and comparable to that of food legumes (peas and lentil). Mushroom protein was deficient in the sulphur containing amino acids, methionine and cystine. It was concluded that the nutritional values of mushrooms can be further improved by dietary supplements, such as milk and its products.