Using a self-design 0.53μm-1.06μm composite laser as the jamming s ource,the jamming effects on CMOS imaging device and semi-active laser (SAL) guidance system are experimentally evaluated in this paper.In the experiment of laser jamming COMS camera,the jam ming effects of composite laser with continuous wave (CW) and 5kHz output are studied.Under tw o cases (with and without laser jamming protection),the effective jamming area curves of composite laser and mo no-wavelength laser are compared.The results show that with laser jamming protection,the effective jamming area of composite laser is enlarged significantly by up to 60% and 53.1% compared with that of the single wavelength laser.In the experiment of laser jamming SAL guidance system, the preprocessed signals under two jamming conditions (high-repetition composit e laser jamming and high-repetition 1.06μm laser jamming) are compared.The results s how that high-repetition composite laser can disturb the preprocessed signal effectively with a decrease of waveform correlat ion up to 25.1%.