Abstract: The Terrestrial Ecosystem Carbon Inventory Satellite（TECIS），nicknamed “Goumang” ，is supported by the China National Civil Space Infrastructure Program.It focuses on evaluating the carbon sink of forests，and is equipped with 4 payloads including Carbon Sinks and Aerosol LIDAR（CASAL），Directional Multi-Spectral Camera（DMC），Fluorescence Spectral Imager（FSI）and Directional Polarization Camera（DPC）.Adopting diversified remote sensing of lidar，multi-direction，multi-spectrum，hyper-spectrum and polarization，aboveground biomass（AGB），solar-induced chlorophyll fluorescence（SIF）and aerosol content can be measured quantitatively by the combination of active and passive remote sensing.Retrieval products of TECIS are published after calibration and validation.The precision of forest mean height is better than 1.5m where ground slope is less than 5°.AGB products in regional scale are inspected to be better than 85%.TECIS will provide remote sensing service in investigating the carbon sink，ecological conditions and resources，and evaluating national major ecological projects.It will play a vital role in the carbon peaking and carbon neutrality goals of China.

Key words: Terrestrial Ecosystem Carbon Inventory Satellite（TECIS）, Goumang, carbon sink of forests, aboveground biomass （AGB）, solar-induced chlorophyll fluorescence（SIF）