The invention discloses a power quality integrated management device of an electrified railway traction supply network. The power quality integrated management device comprises an APF branch circuit and an HPF branch circuit. The APF branch circuit comprises a connecting electric reactor, a controller, more than one set of APF converter and more than one set of charging circuit corresponding to the APF converter. After being connected with the charging circuits, the APF converters are connected to a contact network through the connecting electric reactor in a hanging mode. The APF converters are cascaded through more than two power units, the controller is connected with the APF converters and sends a control signal to switch components of the power units, single-phase uniform amplitude alternating-current PWM output voltage is generated, and an expected current injection contact network is obtained through the connecting electric reactor. According to the HPF branch circuit, a second-order resonance circuit is composed of a resistor, an electric reactor and a capacitor. The power quality integrated management device can provide idle work support for an electric railway traction power supply system, the power factor is improved and meanwhile negative sequence components, harmonic waves, voltage fluctuations and voltage flickers in the system are effectively restrained.