A manual air pump comprises a base, operating rods, connecting rods, a moving block and a cylinder, wherein a piston and a piston rod are assembled in the cylinder, the base is arranged at one end of the cylinder, an air outlet is arranged at the other end, the operating rods are hinged to two sides of the base, a piston hole is formed in the base, the piston rod is assembled in the piston hole and fixedly connected with the moving block, two sides of the moving block are hinged to the operating rods through the connecting rods, an axial stepped hole and a radial air inlet hole are formed in the middle of the piston rod, a valve core and a spring are placed in the axial stepped hole, a plug is fixedly connected with the spring, a through hole is formed in the middle of the plug, and the air outlet is connected with an air pipe provided with a check valve. The manual air pump is reasonable in structure, independent of electric drive and suitable to perform air charge, air supply and the like on tires of field passenger vehicles, motorcycles and small and medium-sized trucks and brings great convenience to life of people. Besides, the air pump can be simply transformed into a hydraulic pump to realize functions of oil pumping, water pumping and the like.