Abstract: The paper presented here have introduced the principles and characteristics of several QTL(Quantitative trait locus) analysis methods in plant, including the single-marker QTLanalysis, the interval mapping and the composite interval mapping. The single-marker QTLanalysis is based on the sub-groups of marker genotypes to do the significance analysis of average values and the one-way analysis of variance. The interval mapping is used to estimate the probability of having QTLat any position in the interval between any two adjacent markers. The composite interval mapping has been developed on the basis of the interval mapping with use of multiple regression model in the ma- ximum likelihood estimate, and thus may give high accuracy and power in mapping QTLs due to the control over large number of background genetic variation in studying population. Especially in mapping QTLs with epistatic effects and QEinteraction, some extensive ways of the composite interval mapping can produce more reliable results