Disclosed are a terminal block assembly (10) and its wiring wrench (2). The wiring wrench (2) includes a press rod (21) and a handle (22), and the press rod (21) has a pressing protruding arm (211) on a side and a stop portion (212) on the other side, and the handle (22) and the press rod (21) are connected by a pivoting structure (23), and the handle (22) has a clamping protruding arm (221) on a side and an elastic arm (222) on the other side, and the clamping protruding arm (221) and the pressing protruding arm (211) are configured to be opposite to each other, and the elastic arm (222) may selectively abut at the stop portion (212). Therefore, the wiring wrench (2) can be latched securely with the terminal block (1) to provide the effect of latching the terminal block (1) conveniently.