Abstract: In the past two decades, the field of study of mating system and dispersal processes in plants has greatly expanded. Attention has particularly focused on the use of maternal progeny arrays to estimate short-term rates of outcrossing and selfing frequencies, and to examine patterns of pollen dispersal and male fertility variation within populations. Earlier studies relied on exclusion methods but realized that many gene flow events were not being detected by these techniques and that unique parentage could not be determined for a large proportion of the non-immigrant offspring in most natural populations. Consequently, methods for maximum-likelihood estimation of gene flow and male fertility have been introduced. Estimations of relative frequencies of outcrossing and selfing in populations and families based on single-locus and multi-locus models are discussed in this paper. Attention is given to the method of parentage analysis and the estimation of the level of gene flow. As an example, we present our studies of mating system and paternity analysis on Ophiopogon xylorrhizus, an endangered plant in China.