From　perspective　of　subjectivity　of　trust,　a　group　Trust　model　which　is　used　to　depict　constraint　relationships　among　individuals　in　a　particular　group　through　covering　four　basic　constraint　patterns　and　their　nesting;　what＇s　more,　gauging　methods　of　direct　trust　degree　and　recommendation　trust　degree　of　basic　constraint　patterns　and　their　nesting　are　brought　up　based　on　subjective　logic　theory　respectively,　and　these　methods　remarkably　support　group　trust　relationship,　especially　trust　relationship　of　software　groups.　Analysis　on　expressive　power　and　validity　of　group　Trust　model　proves　that　this　model　has　outstanding　adaptability　and　practicability.　©2009　IEEE.