Abstract: In order to monitor present-day crustal motion and internal deformation rule in Guangxi area,repeated GPS campaigns(1998,1999,2003,2004 and 2007) are used to calculate the 3D velocity field relative to ITRF2000,principal strain parameters and the 3D deformation velocities and deformation trends in a regional reference frame.The results show that Guangxi area along south China plate moves anticlockwise in SE-NW direction at the rate of 2.3 mm/a,and the average velocity in east-west direction is 29.3 mm/a,and the average velocity in south-north direction is-13.4 mm/a and the average vertical velocity is 2.3 mm/a.The present-day crustal movement in regional reference frame is relative large(about 4 mm/a),and the principal tensile strain rate(5.48 10-9/a) is larger than the compressive strain rate(3.70×10-9/a),Guangxi area is mainly under the extension strain in the direction of N43.19°E.