The invention relates to mechanical manufacturing equipment, particularly to a mechanical cutting machining device and a corresponding adjustment mechanism. A four-degree-of-freedom fine adjustment base comprises a base assembly; a power head assembly comprises a power head, a cutting tool, a motor and a transmission belt; the cutting tool is connected onto an output shaft of the power head; the motor is connected with the power head through the transmission belt; the base assembly comprises an upper wedge block, a lower wedge block, an upper flat plate, a lower flat plate, a supporting plate, a pushing plate, a cushion plate group, a fine adjustment bolt group, a locking bolt group and a thrust bolt. According to the power head assembly and the four-degree-of-freedom fine adjustment base, the power head assembly is fixedly connected onto the four-degree-of-freedom fine adjustment base, the mechanical cutting machining is implemented through the power head assembly, the function of fine adjustment along four degrees of freedom is achieved through the four-degree-of-freedom fine adjustment base, the precision adjustment on the power head assembly is implemented through the four-degree-of-freedom fine adjustment base, and accordingly the precision positioning is rapid and the efficiency and the quality of equipment installation are improved.