The invention discloses a valve capable of adjusting the flow and an adjustment method of the valve and relates to the technical field of valve equipment. The valve comprises a shell, a sliding shell,a water outlet, a water inlet pipe, a rotating handle, a driving assembly, stop blocks, connecting rods and an elastic component. The sliding shell is slidably contained in the shell. The two side walls of the sliding shell are closely attached to the two inner side walls of the shell. The upper end and the lower end of the sliding shell are symmetrically provided with openings, so that a fluid flow channel is formed. The water outlet is fixedly arranged at the lower end of the shell and communicates with an inner chamber of the shell. The water inlet pipe is fixedly arranged at the upper endof the shell and communicates with the inner chamber of the shell. The rotating handle is in threaded connection to the water inlet pipe. The driving assembly is arranged below the rotating handle. The output end of the driving assembly acts on the sliding shell. The two stop blocks can perform horizontal face-to-face or opposite sliding in the sliding shell. One end of each connecting rod is hinged to the inner side wall of the shell, and the other end of each connecting rod is hinged to the corresponding stop block. The elastic component is arranged between the sliding shell and the shell.