PROBLEM TO BE SOLVED: To provide a safe, accurate, and highly sensitive method for evaluating disinfection effect to acanthamoeba.SOLUTION: An evaluation method of disinfection effect to acanthamoeba which includes processes (1) to (4) below. (1) a process of culturing acanthamoeba which underwent disinfection treatment by using a culture medium containing a hydrolysate of milk protein or an extract of animal tissue other than stomach as a main component in the presence of 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT); (2) a process of capturing the cultured acanthamoeba in a solid phase; (3) a process of extracting MTT formazan from acanthamoeba, which was captured in the solid phase, by adding physical stress to the solid phase to apply 3,5-diphenyl-1-(4,5-dimethyl-2-thiazolyl) formazan (MTT formazan) soluble solvent; and (4) a process of evaluating disinfection effect of the disinfection treatment to acanthamoeba based on an amount of the extracted MTT formazan.SELECTED DRAWING: Figur
