The optical interconnection speed of data center is developing rapidly in recent years. As for the optical interconnection of data center, a compact, low-loss, and small output mode field four-channel coarse wavelength division demultiplexer chip is designed and fabricated, which is using quartz-based silica optical waveguide with 1.5% refractive index difference. This chip can meet the transmission velocity requirement of 200 Gbit·s ^-1/400 Gbit·s ^-1 for high-speed data center. The minimum insertion loss is less than 1.07 dB, the 1 dB bandwidth is larger than 13.7 nm and the 3 dB bandwidth is larger than 16.1 nm. The polarization-dependent loss is smaller than 0.08 dB, the adjacent crosstalk is larger than 24 dB, and the non-adjacent crosstalk is larger than 30 dB. The designed chip can fully meet the commercial requirements of a wavelength division demultiplexer chip for optical interconnect of high-speed data center.