— We have designed and implemented the LDPC decoder chip with memory-reduction method to achieve high-throughput and practical chip size. The decoder decodes (3,6)-2304bit regular LDPC codes using modified min-sum algorithm. The decoder achieves a throughput of 530Mb/s at an operating frequency of 147MHz. The chip has been fabricated in a 0.18µm, 6 metal-layer CMOS technology. The chip size is 36mm2 .