To improve the stability and tritium permeation resistance of the AlN single-layer coating, a Ti-AlN system coating is proposed. Ti/AlN/Ti/AlN multiple coatings with a total thickness of about 500 nm were prepared on the substrate surfaces of 316L stainless steel by magnetron sputtering. The coated samples were heat-treated under different conditions, and the microstructure and phase composition before and after heat treatment were analyzed by SEM, XRD, and AES. The deuterium permeation experiment was then conducted for all the samples. The results show that only some amount of Al3Ti products are formed at the Ti-AlN interface for all the coated samples heated at 700 ℃ or 760 ℃ for 4 h. Among all the coated samples, the coated sample with a heating temperature of 700 ℃ and heating rate of 1.5 ℃/min exhibits the best deuterium resistance performance, and its PRF (Permeation Reduction Factor) value at 600 ℃ is 536. When the heating temperature is increased to 760 ℃ or the heating rate increased to 2.5 ℃/min, the cracking of the coating will be aggravated, which lowers the deuterium permeation resistance. On the other hand, with the decrease of the penetration temperature, the PRF values of all the coated samples also decreased sharply, indicating that the deuterium gas penetration process had an obvious failure effect on the coating structure, the mechanism of which needs to be further studied.