In the present study, using High Pressure Liquid Chromatography (HPLC) and Gas Chromatography Mass Spectometry (GC/MS), sulfur compounds, flavonoid compounds and saponin compounds of the shallot bulbs, colleted from Vinh Chau town (Soc Trang province, Go Cong district (Tien Giang province), Ly Son island (Quang Ngai province) and Ninh Hai district (Ninh Thuan province), were investigated. Results showed that specific sulfur compounds of onion, including isoalliin, allicin, violatile sulfur-contanining compounds (dipropyl disulfide, dipropyl trisulfide, methyl propyl trisufide) and S-propenyl-cysteine, a water-soluble compound, were existed in the shallot bulbs. In especially, the sulfur compounds precursor, isoalliin, in Vinh Chau shallot, collected from the main-shallot crop, was highest among the shallot samples, at 411.3 mg/100 g. The flavonoids, including anthocyanin, quercetin and kaeferol, were indicated in entire shallot and took a highest content in Vinh Chau shallots in comparion to the other shallot samples. In addition, saponin and sapogenin were also determined in the shallots. Sapogenin content was quite similar in the shallot samples, from 5.4 to 6.6 mg/100 g, however, highest saponin content were recored in Vinh Chau shallot samples. Taken together, these finding shed light on the effects of shallot as spice and for the treatment of many diseases.