Mycorrhizal colonization had significant effect on cluster bean root length at different salinity levels. The results showed that total root length of mycorrhizal inoculated plants decreases as salinity level increases. In the present study, maximum root length was observed in plants treated with G. mosseae at 4 dSm-1, 8 dSm-1 and 12 dSm-1 salinity level respectively followed by G. mosseae + A. laevis combination. Our results support the findings of Quilambo (2000) who observed significant increment in root length in peanut inoculated with an indigenous AM fungi at various salinity levels. Similarly Shekoofeh and Sepideh (2011) observed that mycorrhizal inoculated Ocimum basilium plants grown under saline conditions experienced an increment in root length in association with higher vacuolar Na acts as osmoticum enabling the plants to maintain high water potential and allow them to have more open stomata, greater CO2 assimilation in the absence of any disruption of photochemical events, and more sucrose accumulation. It seems that root growth is increased by increasing mycorrhizal inoculation of plant root and providing a desirable limitation of phosphorus. Correlation of root length with mycorrhizal inoculation amount of root is probably related to suitable ventilation of soil, that is the result of hypha network of mycorrhizal fungi that connects particles of soil and as result the root spreads into deep soil (Turk et al., 2006).