The experimental results of low frequency optical noise and electrical noise andtheir correlation of 1. 3 μm InGaAsP/InP superluminescent diodes fabricated by us aregiven. These results are analysed and discussed in combination with electrical derivative,optical derivative and spectrum measurement. The results demonstrate that the lowfrequency optical noise and electrical noise of superluminescent diedes are correlative, andthe noises are related to the material quality of the dieodes, structure parameters and operation conditions.