Wheatstone bridge and AC bridge experiments are important parts in middle and higher experimental educations．In view of simple principle of the circuits and weak experimental operational ability for students，we adopted modularized circuit and color wire marking methods to greatly give the deep insight into the experimental circuit structures and to improve the efficiency of the building circuits． The method makes students mainly focus on experimental phenomena and experimental law and greatly improve the teaching efficiency．So the method can be extended to other similar or more complex circuit experiments．