A nesting box structure of a bird cage, which is used in conjunction with a bird cage, and can be assembled on the outside of the bird cage or inside the bird cage in accordance with the installation method, thereby improving the variability of the installation of the structure and the import and export through the configuration of the nest box body. The bird is provided to enter and exit the nest box body and the bird cage, and the inlet and outlet are further provided with a protection unit to prevent the bird from being scratched by the sharp edge of the inlet and outlet, and to improve the safety and smoothness of the bird to enter and exit. The nest body is additionally provided with a hole for arranging a temperature and humidity meter, so that the owner can pay attention to the temperature and humidity of the habitat space at any time, and the bird can lay eggs or hatch to adjust the living conditions of the habitat. The environmental conditions of the habitat can be mastered to increase the stability of bird hatching and life, and there are progressive upgraders.一種鳥籠之巢箱結構，其係配合一鳥籠設置使用，可配合安裝方式組設於鳥籠外側或是鳥籠內部，提升結構安裝之變化性，並透過該巢箱本體配置之進出口提供禽鳥來回進出巢箱本體及鳥籠間，且該進出口更套設有一保護單元，避免禽鳥受到進出口邊緣尖銳處劃傷，同時提升禽鳥來回進出之安全性及順暢度，且該巢箱本體另設一穿設孔搭配設置一溫、濕度計，令飼主可隨時注意該棲息空間之溫度及濕度，並可禽鳥產卵或是孵蛋狀態去調整棲息空間的生活條件，令該棲息空間的環境條件可被掌握而增添禽鳥孵化、生活之穩定性，實有進步性的提升者。
