Determination and separation of six water-soluble vitamins including (B1, B2, B3, B5, B6, B12) on reversed –phase BDS- C18 (250X4.6 mm id) column were done. Data show that mobile phase containing heptane sulphonate (1.5mM as solvent (A) and mixture of phosphate as buffer B, as ion –pairing reagent, prove excellent separation. The high performance liquid chromatographic method has proved to be rapid and accurate.The results show the highest concentration belongs to B3 in all types of aqueous garlic extracts but the highest-level concentration is in Iraqi garlic extract (15.58) ppm. The detection limits of Niacin were between ((0.001 –0.125 )ppm) for (B6–B3, B12) respectively.