The invention discloses a high-voltage direct connection type electricity stealing detection device. A signal collecting and sending module is composed of a 10-kilovolt high-voltage current and voltage collecting unit, a data merging unit and a wireless signal sending unit which are sequentially connected. A signal processing module comprises a control processing core, a primary data interface, a secondary data interface, a master station data interface and a human-computer interface which are respectively connected to the control processing core. The wireless signal sending unit of the signal collecting and sending module is connected to the primary data interface of the signal processing control module through a wireless channel, and the master station data interface of the signal processing control module is connected to a master station system through the wireless channel. The signal collecting and sending module is fixedly connected to one end of a retractable insulating rod. According to the high-voltage direct connection type electricity stealing detection device, a user secondary side metering device and the electricity stealing behavior in a loop can be fast, accurately and conveniently detected and judged, an alarm can be given timely, various electricity stealing behaviors are effectively eliminated, and a basis is provided for supplementing the electric quantity.