The invention discloses a hollow testing and adjusting integrated polymer injection device which comprises a throttling outer working tube, a lower center pipe, an adjusting core, a flow guiding pipeand a puncture-resistant piston. The lower end of the throttling outer working tube is connected with the upper end of the lower center pipe, the adjusting core is arranged in the throttling outer working tube, and an inner annulus is formed between the adjusting core and the throttling outer working tube. The flow guiding pipe is arranged outside the throttling outer working tube, and an outer annulus is formed between the flow guiding pipe and the throttling outer working tube. An upper liquid inlet hole communicating with the inner annulus is formed in the upper end of the adjusting core, and a lower liquid inlet hole communicating with the inner annulus is formed in the lower end of the adjusting core. A flow passing hole communicating with the inner annulus and the outer annulus simultaneously is formed in the throttling outer working tube, the lower center pipe is sleeved with the puncture-resistant piston, and a pressure cavity is formed between the puncture-resistant piston andthe lower center pipe. A radial hole communicating with the pressure cavity is formed in the lower center pipe. According to the hollow testing and adjusting integrated polymer injection device, an adjusting mechanism is stressed in a balanced mode under the large throttling differential pressure, and the problems that in the switching adjusting process, due to change of the throttling differential pressure, the adjusting torque is large, and even, adjusting cannot be conducted can be effectively avoided.