Abstract: An experiment was conducted to evaluate the effects of row spacing (RS) and inter row spacing (IRS) on some agro-physiological traits of 2 common bean (Phaseolous vulgaris L.) cultivars, at the agricultural research area, Faculty of Agriculture, University of Urmia, Iran during 2003. Experimental design was a factorial split-plot based on randomized complete block design with 3 replications. The 30, 45 and 60 cm of RSs constituted the main plots and IRSs of 5, 10 and 15 cm and cultivars of Derakhshan and Naz (determinate and indeterminate, respectively) were allocated to the sub plots. Obtained results showed that different RSs and IRSs affected the Grain Yield (GY). The highest GY was recorded at 30 cm RS (4.191 t ha-1) and 5 cm IRS (3.926 t ha-1). The number of pods plant-1 (NPP), the number of grains plant-1 (NGP) and grain weight plant-1 (GWP) increased as a result of a decrease in the RS and IRS. In addition, it was observed that by increasing the RS and IRS the first pod trait had higher height. However, the Grain Protein Content (GPC) was not affected by the IRS and RS changes. On the other hand, Naz (indeterminate) had higher capability for the grain yield than Derakhshan (determinate) cultivar.