Buckwheat (Fagopyrum esculentum Moench.) is an alternative crop belonging to the Polygonaceae family. Buckwheat has been well known as a plant source of rutin, quercetin, kaempferol-3-rutinoside and other phenolic compounds. Buckwheat contains more rutin than most of the other plants, which exhibits antioxidative, antihemorrhagic and blood vessel protecting properties. Phenylalanin ammonia-lyase (PAL), chalcone synthase (CHS), flavone 3-hydroxylase (F3H), and anthocyanidin synthase (ANS) were important enzymes involved in the flavonoid biosynthesis in buckwheat. In this study, we have purified full-length PAL, CHS, F3H and ANS from buckwheat using RACE PCR with degenerated primers targeted to conserved regions of orthologous sequences PAL, CHS, F3H and ANS available. The open reading frame of FePAL was 2112 nucleotides long, encodes for 704 amino acids. FePAL gene shares 80-81% identity and 88-90% similarity with Arabidopsis thaliana PAL1, Capsicum annuum PAL, Lactuca sativa PAL, and Populus trichocarpa PAL2. The cDNA of FeCHS has 1179 nucleotides open reading frame, encoding for 393 amino acids. FeCHS has identities and similarities ranging 84-86% and 92-95%, respectively, with other CHSs from P. trichocarpa, Citrus sinensis, Gerbera hybrid, and Vitis rotundifolia, whereas this gene shares 93% identity and 98% similarity with Polygonum cuspidatum. The cDNA of FeF3H has 1101 nucleotides open reading frame, encoding for 367 amino acids. FeF3H has identities and similarities ranging 76-81% and 92-97%, respectively, with other F3Hs from Gossypium hirsutum, Dimocarpus longan, Garcinia mangostana, Camellia sinensis, Vitis vinifera, Rubus coreanus, Pyrus communis, Glycine max, and Actinidia chinensis. The open reading frame of FeANS was 1074 nucleotides long, encodes for 358 amino acids. FeANS gene shares 74-76% identity and 94-96% similarity with Gypsophila elegans, C. sinensis and G. hirsutum. These result provieded the theoretical basis for the metabolic engineering on buckwheat.