A network cable plug with a falling-off prevention structure includes a plug body (1), a connecting sleeve (2), and a stopper plate (3). The plug body (1) is inserted into a network socket (6). The connecting sleeve (2) is connected to the plug body (1). The stopper plate (3) can be inserted into the connecting sleeve (2) to a locking position. In the locking position, a stopper portion (31) of the stopper plate (3) is located below and abuts an elastic clip (13) to prevent the elastic clip (13) from being pressed downward, and a bottom protrusive portion (33) of the stopper plate (3) is engaged in a fixing hole (25) of the connecting sleeve (2). The stopper plate (3) is bendable upward to disengage the bottom protrusive portion (33) from the fixing hole (25), permitting the stopper plate (3) to move rearward to disengage from the elastic clip (13).