Receiver filter bandwidth (RFB) of satellite laser altimeter (SLA) resolves the key performances of SLA. According to the operational principle of SLA, the theoretical models of received signal and receiver signal-to-noise ratio (SNR) are established, and the mathematical expressions about range error, probability of detection and false alarm are deduced. Under the condition that probability of detection and false alarm can satisfy the threshold, an optimizational design method for RFB on the basis of minimizing the range error is put forward. As an example of MOLA-2, the distributions of RFB and range error related with different target slope angles are simulated. The results show that the optimizational design values of RFB are larger than values given by conventional method within 40° target slope angle, whose difference limits the scope from 0.7 MHz to 58.7 MHz. However, corresponding range errors are less than them obtained by conventional method, the extent of their difference is 0.2~16.2 m. With the restrictions of target variety and complexity, it is difficult to make every target correspond with a receiver filter during its manufacture, so multiple receiver filter channels are set up to piecewise fit the distribution curve of range errors, the RFB and corresponding scope of target slope angle for each channel are achieved. The optimizational method of designing the RFB provide a superior and practicable scheme for manufacturing receiver filter.