Disclosed is a packet data processing apparatus which processes packet data in a packet data serving node. In the apparatus, a separate hardware configuration of a PDSN performs de-framing and de-stuffing for a PPP frame provided from a BTS, thereby generating an IP frame, and then outputs the generated IP frame to the Internet network. Further, another separate hardware configuration of the PDSN frames and stuffs an IP frame transferred from the Internet network, thereby generating a PPP frame, and then transfers the generated PPP frame through the BTS to corresponding MS. Therefore, processing speed of a line card performing interfacing with the BTS, and the performance of the entire PDSN can be improved. Moreover, problems due to data processing are prevented from being caused, since many functions in relation to PPP have been realized by hardware.