The results of 128×128 SW/MW twocolor HgCdTe infrared focal plane arrays (IRFPAs) were presented. By B+implantation, mesaisolation etching, sidewall passivation, sidewall metallization and flipchip hybridization with readout integrated circuit (ROIC),128×128 SW/MW twocolor HgCdTe IRFPAs detector was fabricated from a fourlayer ppPN heterojunction of Hg1-xCdxTe film grown by molecular beam epitaxy and insitu doping techniques. The micromesa fillfactor of (50×50)μm2 twocolor detector arrays was doubled by optimizing the wetchemical etching process. The staring SW/MW twocolor HgCdTe IRFPAs detector performed high uniformity and normal photoelectric properties. At liquid nitrogen temperature, the cutoff wavelengths of the twocolor IRFPAs were 2.7μm and 4.9μm, respectively, and the peak detectivities (D*λp) were 1.42×1011cmHz1/2/W and 2.15×1011cmHz1/2/W respectively. 