The utility model discloses a portable well cellar machine adopting a controllable water making method, belongs to the technical field of agricultural machinery, and overcomes the defect that a tobacco grower lacks a well cellar machine which is convenient to carry and good in cellar forming quality in the planting process in the prior art. The device mainly comprises an L-shaped operating rod, the L-shaped operating rod is a hollow rod; the L-shaped operating rod comprises a vertical operating rod and a horizontal operating rod; a water pipe is mounted at one end of the horizontal operating rod; a drill is mounted at one end of the vertical operating rod; a cavity is formed in the drill bit; the drill bit comprises a positioning cover, a cylinder and a conical head, a water outlet is formed in the conical head, the forming direction of the water outlet is parallel to the vertical operating rod, a holding rod is installed on the upper side of the vertical operating rod, a distance fixing device is installed on the lower side of the vertical operating rod, the distance fixing device comprises an L-shaped positioning rod, and the L-shaped positioning rod comprises a horizontal positioning rod and a vertical positioning rod. The well cellar building device is used for building a well cellar during flue-cured tobacco planting.