The study aimed to evaluate the effects of N-K concentration in the nutrient solution on the growth, yield, and physiological characters of two bush snap bean cultivars. ‘Torukatto’ exhibited a longer vine than 'Super Light Green.' 'Super Light Green' had a larger canopy, more leaves produced, greater leaf area, more shoots developed, and heavier shoot fresh and dry weights. 'Super Light Green' produced a few flowers and low pod number and yield. 'Torukatto' had a higher percent pod setting, but 'Super Light Green' had a heavier weight per pod. There was a significant influence of N-K levels on leaf area and number of shoots produced. Increasing the N-K level slightly increased the leaf area. 'Torukatto' had significantly higher SPAD values and rate of net photosynthesis than that of ‘Super Light Green’. The stomatal conductance and transpiration rate differed significantly between the cultivars. Increasing the N-K level markedly improved the physiological measurements at a slightly increasing trend. There was a strong correlation between yield and number of pods and between photosynthesis and leaf color.