The invention relates to a locking-force-adjustable rotational joint. The locking-force-adjustable rotational joint comprises a rotary housing and a supporting inner frame, wherein the middle part ofthe supporting inner frame is coaxially fixedly connected with an oil filling pipe; a plurality of oil discharging pipes are connected in annular arrays to the sidewall of the oil filling pipe; N groups of oil discharging holes are arranged in annular arrays in the external sidewall of the supporting inner frame; a sealing block is arranged inside the supporting inner frame; the sealing block is fixed to the position of the corresponding oil discharging hole in the inner wall of the supporting inner frame; an annular spring piece is further arranged outside the supporting inner frame; the spring piece comprises N groups of locking bumps and N groups of deformed bumps, wherein the outer wall of the oil filling pipe is rotationally connected with a pulling plate; the pulling plate is provided with N connecting plates; the end part of each connecting plate is provided with a rotating column; each rotating column is rotationally connected with a rotating hook; each rotating hook is fixedly connected to the inner wall of the spring piece; the supporting inner frame is installed inside the rotary housing; and a plurality of embedding grooves are further formed in annular arrays in the annular inner wall of the rotary housing.