Abstract: Different kinds of defects are found in curved composite bonding structures both in manufacturing and in serving stages. Nondestructive testing methods available now are not capable of the in-situ testing of curved composite bonding structure with high speed. Lock-in infrared thermography is characterized by non-contact, large-sized testing area, audio-visual results, et al. It is fit for the in-situ testing of curved composite bonding structure. The best testing conditions of Lock-in infrared thermography are obtained by testing of defects in composite bonding structure samples. The in-situ testing is experimented industrially. It is shown that the lock-in infrared thermography could be applied to curved composite bonding structures in manufacturing, repairing and serving stages.