An ESA technology programme led to the successful development of an aluminum extruded heat pipe family based on a multi re-entrant grooves design and using ammonia as working fluid. This family, called High Capacity Grooved Heat Pipe (HGP), has been submitted to a space qualification programme according to ESA standards (ESA PSS-49; see ref.), which aimed to fulfill an as large as possible range of potential applications. Therefore, four heat pipe diameters (11 mm, 15 mm, 20 mm and 25 mm), two heat pipe outer shapes (circular, saddles integrated) and two heat pipe configurations (straight, bent) have been selected for going into this space qualification. The space qualification programme, started in 1994, ended up early 1997. The present paper presents the HGP heat pipe family characteristics and the space qualification programme. After the review of the requirements and philosophy, the qualification results obtained through the different qualification tests (environment, thermal, performances…) are described and analyzed.