The utility model provides a marine LNG air track is carried to diesel dual -fuel engine air feed, belongs to the transformation of the marine diesel fuel engine energy, is LNG reformed transform into to single diesel fuel power the diesel dual -fuel power technology field. In order to solve the problem in the unable stable entering engine of the natural gas. The utility model discloses an air feed carries air track to link to each other through the gas outlet with gas inlet channel, carries liquefied natural gas to the engine, a N air track's of branch one end is linked together with main air track respectively, main air track and the N air track of a branch structure as an organic whole, a N air track's of branch the other end is the open end to a N air track's of branch open end is linked together with a N gas injection valve 's air inlet respectively, main air track is the cylindrical cavity of one end open -ended, main air track's open end is linked together with gas inlet channel's gas outlet, N is more than or equal to 2's even number. Beneficial effect carries air track's gas tightness good for the air feed, enough satisfied safe, stable requirements to the transport natural gas in the engine.