The precise design and efficient development of nanoscale materials at the atomic level has enabled high‐end renewable energy storage, conversion devices, and large‐scale environmental governance equipment. Atomic layer deposition (ALD) is a new vapor‐phase technology for precise surface thin‐film preparation, and is outstanding with self‐limiting reactions, large deposition area, adjustable film composition, film uniformity, angstrom thickness control and low temperature. With these characteristics, ALD plays an important role in many industry and research fields. This review briefly introduces the principle, main technical advantages and applications of ALD, including high‐k gate dielectrics, solar cells, fuel cells, and photocatalysis. The progress of the ALD technology in preparation and application of photocatalyst is emphatically reviewed, and the large‐scale application of ALD in photocatalytic thin‐film materials is prospected.This article is protected by copyright. All rights reserved.