Two experiments were conducted to study the effect of root-knot nematode, Meloidogyne incognita at three inoculum levels on the growth characteristics of common bean (Phaseolus vulgaris L.) cv. Xera and the response of plants towards the nematode on two different planting dates (Autumn, and Early spring seasons). Data indicated that different M. incognita inoculum levels at the two growing seasons had distinct effects on the growth of common bean. The results revealed that the root galling severity, and damage index (DI) increased significantly (P<0.05) with increasing the inoculum levels of M. incognita on common bean. However, root galling was more severe on common bean plants as the maximum index rate was 8.6 and 9.0, seventy days after inoculation (Pi = 3000 J₂s) in autumn and spring seasons, respectively. Similarly, the final nematode population and egg masses/root increased with increasing the inoculum levels of M. incognita during the early spring season compared with the autumn season. All the growth parameters were significantly (P<0.05) reduced in all infected plants as compared with control (uninfected) plants. At lower initial inoculum levels the extent of reduction in plant growth was low, but at higher inoculum levels, reduction in plant growth parameters was remarkable, in comparison to control plants in the two growing seasons, but more reduction was observed in the early spring season. The highest percent reduction was achieved by inoculation levels 2000 and 3000 J₂s in the whole plant fresh weight, plant lengths, root, fresh weight, pods weights, and number of nodules per root system. With an increase in initial inoculum levels of M. incognita, physiological parameters of common bean were decreased. In response to nematode infection, the data clearly clarified that root-knot nematode adversely affected the plant growth, nitrogen, phosphorus, potassium percentages, total protein and chlorophyll contents in nematode-infected common bean plants.