Co-verification is the key step of software and hardware codesign on SOC. This paper presents a hw/sw co-verification methodology based on TWCNP-OS, a Linux-based operating system designed for FPGA-based platform of two-way cable network (TWCNP) SOC. By implementing HAL (hardware Abstraction level) specially, which is the communications interface between hardware and software, we offer a homogeneous Linux interface for both software and hardware processes. Hardware processes inherit the same level of service from kernel, as typical Linux software processes by HAL. The familiar and language independent Linux kernel interface facilitates easy design reuse and rapid application development. The hw/sw Architecture of TWCNP and design flow of TWCNP-OS are presented on detail. A software and hardware co-verification method using TWCNP-OS is proposed, through the integrated using of Godson-I test board and TWCNP, which realizes the combination of design and verification. It is not a replacement of the co-verification with generic RTOS modeling, but is complementary to them. Performance analysis of our current implementation and our experience with developing this system based on TWCNP-OS will be presented. Most importantly, since the introduction of TWCNP-OS to our FPGA-based platform, we have observed increased productivity among high-level application developers who have little experience in FPGA application design.