The use of the national very high resolution space system Alsat-2A is a primordial task having a significant technological and economical interest assuring the strengthening autonomy in terms of availability and coverage in the satellite data. Also it allows us to improve and update the base and thematic mapping throughout the national territory. Firstly, the characteristics of ALSAT-2A are presented, namely the images and the imaging system with a brief history of ALSAT program. Secondly, as a prerequisite, knowing the internal parameters is essentials to modelize the geometry of such imaging system. From metadata given by the images distributor and ground control points, several test are described and the results are presented. The test data are supplied by ASAL (Algerian Space Agency), the first dataset comprise a panchromatic image over the region of El Bayadh in the North West of Algeria equipped with nine GPS surveyed points. The second dataset is an along track stereoscopic panchromatic 1A level images over the town of sevilla in the south of Spain with 24 GCPs. Finally, a discussion on obtained results is dressed showing the geometric capability of ALSAT-2A.