This study was undertaken at the private Farm, Bani Mazar District, Minia governorate. during the two seasons of 2020 and 2021. The aim of this study was to investigate the effect of irrigation water salinity, mineral and biofertilization [effective microorganisms (EM) and Azotobacter chroococcum bacteria (AC)] treatments, as well as, their combinations on the root growth and some chemical constituents of bermudagrass (Cynodon dactylon, L.), grown in sandy soil. Results showed that the root growth parameters i.e., root length and fresh and dry weights/unit were enhanced with the low and medium levels of salinity (3000 and 6000 ppm), while, they decreased with the high level of salinity (9000 ppm) compared with control, in the third cut during both seasons. On the other hand, all salinity treatments increased Na, Cl, Ca (% in the dry herb) and proline content (in fresh weight), and decreased photosynthetic pigments as well as NPK %. All used mineral and/or biofertilization treatments significantly increased root length and fresh and dry weights/unit comparing with control treatment in 3 rd cut, except AC for root length and EM and AC in case of fresh and dry weights/unit, with the highest values that were obtained due to 100% mineral NPK followed by EM + AC during both seasons. N, P, K and Ca % as well as photosynthetic pigments and proline content were increased due to application with any of the sub-plot treatments, while, Na and Cl were decreased. The best interaction treatments which mitigate the adverse effects of salinity (9000 ppm) were 100% mineral NPK followed by biofertilizer (EM + AC).