Two pot experiments were carried out in the farm of Fac. of Agric.; MansouraUniversity during the two successive summer seasons of 2008 and 2009, to investigate the effect of soil salinity Proline treatments and some irrigation levels on plant growth, yield and biochemical constituents of Common bean (Phaseolus vulgaris L.). cv. Nebrasca. The results obtained can be summarized as follows:- 1-Vegetative growth of common bean in term of plant height, number of leaves, fresh weight, dry weight and leaf area was reduced in case of growing on saline  clay soil in both seasons. 2- Decreasing the number of irrigation gave rise to decrease vegetative growth in both seasons. 3- Proline treatment caused positive effect on the leaves. 4- The triple interaction had no significant effect on all parameters of vegetative growth in both years except leaf area in the second year. 5- Saline soil had deleterious effect on flowering parameters on both years. Likewise, decreasing irrigation number lead to injuring effect on flowering parameters while proline treatment had no obvious increase in this respect. 6- Triple interaction had no effect on flowering parameters on both years. 7- Almost NPK concentrations as well as Na, Ca, Mg were reduced in case of saline soil in both years. 8- Decreasing irrigation number decreased mineral contents of common bean leaves in both years, while proline treatment lead to increase mineral concentration in both years. 9- Saline soil had injurious effect on chlorophyll contents in both seasons. Likewise, decreasing irrigation number caused a significant decrease in pigment content in both years. Otherwise, proline treatment caused an increase in pigments content in both years.