Abstract: Pulsed laser is a new method which can be used to simulate single event effects(SEE)of space exploration payloads. It can locate the most SEE sensitive area of the test devices, and also can dynamically test SEE time response of the circuit system. With test and theory research, the relationship between laser threshold energy of single event upset and single event latch-up with heavy ion linear energy transition(LET)is established. And the laser quantification is obtained through the evaluation of SEE sensitivity of space exploration payloads. It's of great significance for establishing standards of the pulsed laser evaluation and test, and for providing references for further engineering application. The SEE sensitivity and its effects on the circuit system are required to be tested, and suitable circuits are to be designed to avoid SEE. The method for avoiding SEE of the experimental circuit system should be tested, and special ASIC radiation hard circuit should be designed for the space payloads. All mentioned above need fine SEE tests.