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This study was conducted to evaluate the control efficacy of Pseudomonas chlororaphis, Erwinia herbicola, Bacillus amyloliquefaciens, and Bacillus subtilis, as well as solutions of zinc sulfate, sodium malonate, and oxalic acid against potato white mold caused by Sclerotinia sclerotiorum under field conditions during growing seasons of 2017 and 2018 in Bahar and Lalehjin, Hamedan, Iran. The results showed that strains of Bacillus subtilis as well as zinc sulfate had the highest inhibitory effect against carpogenic germination of sclerotia. The myceliogenic germination of sclerotia was inhibited by solutions of zinc sulfate and sodium malonate with statistically similar results followed by oxalic acid. In addition, activities of resistance-related enzymes including β-N-acetyl hexosaminidase, endochitinase, chitin 1,4-β-chitobiosidase, β-1,3-glucanase, phenylalanine ammonia lyase, polyphenoloxidase, and peroxidase markedly increased in potato leaves due to application of bacteria on plants. The results showed that all treatments were able to reduce significantly (P< 0.05) the number of infected and dead plants in both years. The mixtures of five bacterial biocontrol agents and solution of zinc sulfate were found to be the most effective treatments to control white mold.