Cultivation of green onion has been developed widely in Tran De district, Soc Trang province, contributing to upgrade household income, however salt invasion has caused a decline in green onion production. The study aimed to determine the efficiency of salt tolerance bio-product NPISi (NPISi) on soil characteristics, growth and yield of green onion when grown on salt-affected soil in Tran De district, Soc Trang province. The experiment was carried out in a randomized complete block design with four treatments and four replicates of each treatment. Properties of soil chemistry and biology, growth and yield of green onion were collected. The result indicated that the treatment with NPISi or organic fertilizer (OF) had significantly higher values of NH4+, NO3-, P2O5, nitrogen fixing bacteria, phosphorus, and silicate solubilizing bacteria in soil than in the positive control treatment with 100%NPK, moreover, the total nitrogen, phosphorus, potassium, and silicon concentration in green onion bulb were also higher than the control. The best performance of green onion was observed in treatment applied with both OF and NPISi. Additionally, the inoculant in NPISi product excellently grew, boosted green onion height and yield under salinity condition, especially when associated with OF, green onion yield was enhanced up to 56.0% as compared to the positive control treatment. Therefore, NPISi product is recommended to be used for crops grown on saline soils.