Under the support of the project ‘space environment effects experimental platform of component in CAS’, Space Environment Effects Laboratory (SEEL) has obtained a series of progresses on space environment effects analysis and design technique for spacecrafts. Based on Pro/ENGINEER CAD software, SEEL independently developed a new technique for calculating three-D radiation dose, which is high efficiency analysis algorithm for transmission of particles calculating in spacecrafts. SEEL has gained precise analysis capability in total ionizing dose effect, displacement damage effect, single particle effect and deep charging effect. What’s more, SEEL has successfully developed a space environment effect analyzing software called ‘SEEAP’. Radiation shield of spacecrafts can be optimized by the software, the total ionizing dose can be easily decreased by about 40% at same mass cost. The software have been used in many space missions of Aerospace Science and Industry Corporation, Aerospace Science and Technology, and Chinese Academy of Sciences.