The invention relates to a series compensation device for a box-type distribution network, which comprises a controller, a measurement device, a protection device, a capacitor bank and a vacuum circuit breaker, wherein the controller, the measurement device, the protection device and the capacitor bank are arranged in a box body, the vacuum circuit breaker is arranged outside the box body and connected to a distribution line, and two ends of the vacuum circuit breaker are respectively connected with an isolating switch I and an isolating switch II; the top of the box body is equipped with a wall-through bushing connected with the distribution line, and the capacitor bank is connected in the distribution line through the wall-through bushing; the protection device comprises a damping reactance resistor connected with the capacitor bank in parallel, and the damping reactance resistor is of a split structure and comprises a resistor and a reactor connected to the wire inlet end and the wire outlet end of the resistor. According to the invention, the distribution line can be introduced into the box body through the wall-through bushing, thereby saving the complex procedure of manufacturing a cable joint on site, avoiding the arrangement of a cable trench for wiring at the same time, improving the site installation efficiency, and saving the construction cost.