The invention discloses a remote sensing satellite TDICCD camera integral time on-satellite optimizing and calculating method. The method specifically includes the steps of firstly, calculating the conversion matrix of each CCD from a camera coordinate system to a satellite body coordinate system according to the installation position of a camera on a satellite, and storing the matrix as a constant Pk in a memory of a satellite-mounted computer; secondly, calculating the integral time of the first CCD in the first set according to satellite rail data, satellite posture data and camera parameter data; thirdly, calculating the characteristics with many identical intermediate quantities through the integral time of adjacent CCDs, and storing the intermediate quantities calculated through the integral time of the first CCD in the first set; fourthly, optimizing and calculating the integral time of the rest of M-1 CCDs in the first set through the constant Pk in the first step and the intermediate calculation result obtained in the third step; fifthly, repeatedly executing the second step, the third step and the fourth step to calculate the integral time values of the rest N-1 sets.