The invention discloses an adjustable jet device for a jet-type oxygenation bottom improvement pump set and a manufacturing method of the adjustable jet device. The adjustable jet device comprises a sprayer, a hand shank and duckbilled sprayers, wherein the sprayer and the hand shank are fixedly connected, a handle is mounted at the tail end of the hand shank, and a main hand brake and side hand brakes are mounted on the handle; the sprayer comprises a main body and a main body sprayer fixedly connected with the main body, the tail end of the main body sprayer is duckbilled, and one of the duckbilled sprayers is welded at the duckbill part; two side sprayers are mounted on two sides of the main body sprayer and communicated with the main body sprayer, the tail ends of the two side sprayers are both duckbilled, and the rest duckbilled sprayers are welded at the duckbill parts; each duckbilled sprayer comprises a spring, a cover sheet and a bottom sheet, the bottom sheet is welded at the bottom of the duckbill part, two holes are drilled in the centers of the cover sheet and the bottom sheet respectively, one end of the spring is fixed on the bottom sheet through a fixing stay wire, the other end of the spring penetrates the holes in the centers of the cover sheet and the bottom sheet, and the tail end of the spring is connected with an accelerator stay wire which is connected to the main hand brake and the two side hand brakes; a downwardly folded fold sheet is welded at each of two side edges of each cover sheet.