In this paper a 173-bit type II ONB ECC processor for inductive RFID applications is described. Compared with the standard mathematical expressions provided by A. J. Menezes (1993), the formula expressions adopted in the design can save one field multiplication operation in the curve addition. Therefore, the encryption/decryption time is reduced by approximately 7%. Furthermore, the system level architecture of the ECC processor is specially structured and optimized, which makes it faster and less power consuming, and is more favorable for inductive RFID systems.