Provided is an apparatus for detection timeout of each channel, which is a socket connection, in a Transmission Control Protocol (TCP) Offload Engine (TOE) using TCP accelerating hardware, and a method thereof. The timer managing apparatus of the TOE using the TCP accelerating hardware, including: a command register for receiving a command for a retransmission timer or a delayed ACK timer from an embedded processor of the TOE; a finite state machine (FSM) for storing information of a timer in operation by analyzing the command for the retransmission timer or the delayed ACK timer stored in the command register and controlling an entire operation of the timer managing apparatus; and a timeout checker for checking timeout of a timer in operation by using the stored timer information and notifying the timeout to the FSM.