Abstract: Because the flow around afterbody of transport airplane were badly disturbed by using general rear sting support,ventral support became important support form for transport airplane with upswept afterbody in wind tunnel.There are three kinds of ventral support form according to the support point amount,i.e.single point,double point,and three point.In order to reduce the interference of ventral support,a new-style single point ventral support system was designed and developed in FD-09 low speed wind tunnel based on existing underside high angle of attack experimental mechanism.The single point ventral support system has been completed and put in applications in 2011.It was used for the test of transport airplane and unmanned aerial vehicle.The single point ventral support system was consist of angle of attack mechanism, connecting joint,ventral support sting,and internal balance.The characteristics of single point ventral support system included:the system was simple and convenient for practical application, the model could be easily designed,support interference was relatively stable.The mainly per-formance index of single point ventral support system included:the range of angle of attack was-40°~40°,the range of angle of yaw was-30°~30°,the control precision of angle was 0.05°.The forced transition of support sting was obtained by covering nylon nets.In order to measure sup-port sting interference,the mirror support sting was also covered nylon nets for forced transi-tion.The traditional measurement method for the distances between model and floor was re-placed by a new method using grating ruler displacement sensors in ground effect test,and the control precision and test efficiency were greatly improved.The test results showed that the re-peated test precision of single point ventral support system was higher,and some precision index was close to advanced precision index of GJB.The support interference of single point ventral support system were relatively stable,and the mostly interference were small.The support inter-ference of single point ventral support system was less than the support interference of double point ventral support system.