Ninety bean (Phaseolus vulgaris L.) cultivars were grown till maturity in full strength nutrient solution and, after harvesting, analysed for N, P and K in the various organs. Yield potential and N, P and K requirements were estimated by assuming a population of 250 thousand plants per hectare. Major conclusions were as follows: (1) there were striking differences in the mineral composition of the cultivars; (2) leaf analysis should take into consideration the cultivar under study; (3) protein contents in the grain varied from 20.6 to 34.4%, with an average of 27.3%; (4) extraction of nutrients in kg/ha showed the follow ing variation: N-50 to 425; P-20 to 15; K-100 - 262; percentwise export of K was the lowest; (5) yield potential varied from less than 500 kg/ha to more than 5000; (6) higher requirements are not necessarily associated with higher yield potential thereby suggesting differences in nutritional efficiency of the various vultivars.