To fix the test piece and transmit the excitation signals, the fixture used in the vibration test for satellite electronic devices should have a high stiffness and a high fundamental frequency. A series of indexes are proposed for the design in this paper, including the fundamental frequency and the transverse vibration response. By structural optimization, a light plate vibration fixture for the vibration test of satellite electronic devices is designed. The results of the test show that the fundamental frequency is above 2000Hz and the transverse vibration response is less than 10%. Thus this vibration fixture can meet the requirements of the vibration test.