摘要： Metal halide perovskite nanocrystals are emerging as novel optoelectronic materials. Owing to their excellent optical and electronic properties such as tunable band gap, narrow-band emission and high charge mobility, they are quite promising in various fields including liquid-crystal display backlighting, solid-state lighting and other energy conversion applications. However, the intrinsic low formation energy makes them vulnerable to external stimulus, e. g. water, oxygen, heat, etc. Among many methods, swelling-deswelling microencapsulation emerges as one of the most promising strategies to improve their stability. Herein, recent developments and future research directions in swelling-deswelling microencapsulation-enabled ultrastable perovskite(cid:0) polymer composites are summarized. We believe this strategy has great potential to deliver successful perovskite-based commercial products for many photonics applications.