A packet transmission apparatus and method is disclosed. The present invention transmits data packets without relaying a duplicate acknowledgement packet by equipping an indirect acknowledgement timer at a buffer, generating/transmitting the indirect acknowledgement packet of the first arrived acknowledgment packet base on the indirect acknowledgement timer and implementing an indirect acknowledgement method to a snoop protocol for overcoming problems of the transmission control protocol (TCP) in the wireless network environment. The present invention effectively utilizes resources of the wireless link, which is wasted during recovering lost packet in the conventional snoop protocol. The present invention also reduces a required size of the buffer of the base station by allowing a partially-generation of the indirect acknowledgement packet.