The invention relates to a brewing method of multiple-grain-starter fen-flavor liquor, and belongs to the technical field of liquor brewing. The brewing method comprises nine steps of burdening, soaking, primarily steaming, braising, re-steaming, spreading the grains, feeding the starter, boxing, saccharifying, distilling and aging. On the basis of the traditional brewing method of the multiple-grain fen-flavor liquor, a secondary cultivation saccharification step and a special aging method are mainly added. The taste of the traditional brewed liquor is changed, the original dry, hot and slightly-bitter taste is changed to freshness, simplicity and elegancy, the taste is sweet and thick, and the after-taste is long, smooth, fresh, pure and soft. By adopting the secondary cultivation saccharification, essence in grains can be sufficiently extracted, the yield and quality of the liquor are improved, the resource is saved, the economic benefit is greatly improved, and easiness in popularization and application can be realized.