Linkage disequilibrium (LD) is one of the most recently focused interests in the field of plant genomics. LD mapping is an effective approach to discovering novel genes and a bridge for connecting structural genomics to phenomics. LD mapping was first applied in plants in 2001. Since then, researches on the structure and extent of LD and LD mapping have been reported in a wide range of plant species. The basic theory of LD and its application in LD mapping, haplotype diversity analysis, htSNP identification and population genetics were reviewed in this paper. And advances of LD research in plants including influences of population structure, gene conversion, epistasis and GxE interactions, and future prospects were also presented. China has abundant germplasm resources, but gene discovery lags behind. Intensive researches on LD will certainly accelerate rapid development of plant genomics, especially the progress of gene discovery based on germplasm resources in China.