A method for the determination of amylose and amylopectin content in mung bean was established based on dual-wavelength spectrophotometry. The factors influencing the photometric absorption were also investigated. The precision of the method and the recovery of standard addition were investigated as well. The determination and reference wavelength of amylose were 610 nm and 498 nm, respectively, and that of amylopectin were 553 nm and 709 nm, respectively. The precision of the method was appropriate. The average recovery of amylose and amylopectin were 94.10% and 90.94%, respectively. The regression equation was established to calculate the amylose and amylopectin content in 3 kinds of mung bean being 11.70%~12.67% and 32.70%~34.22%, respectively.