Abstract: the　scientific 　instruments 　on　the 　jade　rabbit 　include 　a　pair 　of 　pancams　desi gned　with　narrow　fields 　of 　view　and 　long－focus．because 　the 　li ght 　beams 　incident 　angle 　of 　this　kind 　of 　lens 　is 　relativel y　smallif 　a　camera 　is 　calibrated　by　the 　traditional 　pers pective　pro jection　modelthe 　coefficientmatrix　of 　its 　normal 　equation　maybe 　ill －conditioned．a　calibration　approach　based　on　orthogonal　projection　model　is 　proposed．experimental 　results 　reveal 　that 　this 　approach　can　be　used 　in 　calibration　ofthe 　jade　rabbit　pancams　with　hi gh　accurac y　and　stabilit y．