Abstract: Background and Objective: Ginger is well known for its medicinal and preservative values but its use for inhibition and dispersion of E. coli O157:H7 biofilm has not been sufficiently explored. This study was therefore designed to evaluate the biofilm inhibition and dispersion activities of Zingiber officinale crude extract and fractions on biofilms of E. coli O157:H7 isolated from dispensed powdered milk in Ibadan, South-West Nigeria. Materials and Methods: Ginger root samples were obtained, identified (UIH-22558), extracted, fractionated using four solvents (hexane, chloroform, ethyl acetate and ethanol) and concentrated. Three E. coli O157:H7 isolates were obtained from dispensed powdered milk and a reference strain (E. coli ATCC 35218) was obtained from the Department of Microbiology laboratory, University of Ibadan. Modified crystal violet assay was employed to develop biofilm and to test the effect of plant extracts on biofilm formation and biofilm dispersal. Results: All the isolates developed biofilm (0.08±0.07) and biofilm dispersion was exhibited with the ethanolic (0.04±0.05) and crude extract fractions (0.05±0.06) having the highest effect, while chloroform fraction had little or no effect at 50 mg mL–1 concentration. Conclusion: Ginger (Zingiber officinale) showed potential use for dispersion of already formed biofilm by E. coli O157:H7 strains, hence, can be used in food processing plants, surfaces and industries to combat biofilm-forming organisms, disperse their biofilms and enhance food safety.