According　to　colorimetry,　the　matching　principle　of　white　LED　based　on　two　primary　color　LEDs　is　introduced;　Using　color　matching　calculation,　the　coverage　of　the　primary　color　LED＇s　chromaticity　coordinate　and　the　coverage　of　the　ratio　of　the　primary　LED　are　determined.　Luminous　efficacy　and　color　rendering　of　white　LED　based　on　two　color　LEDs　are　discussed　and　analyzed.　White　LEDs　based　on　two　primary　color　LEDs　have　the　maximal　luminous　efficacy,　but　their　color　rendering　are　very　poor,　white　LEDs　based　on　primary　LEDs　with　dominant　wavelengths　about　450　nm　and　572　nm　have　the　maximal　k,　400　lm/W,　which　is　approaching　the　theoretic　maximum　of　equality　energy　white　point.　White　LEDs　with　dominant　wavelengths　about　480　nm　and　580　nm　have　the　maximal　Ra,　16.2.