Abstract: The four-in-one model courtyard ecosystem in Northern Liaoning includes four components:sunlight greenhouse,warm pig house,toilet and biogas digester.The results of the study indicate that the four-in-one courtyard ecosystem has a good function on temperature raising and maintaining.The energy efficiency of this ecosystem is much better than that of a single sunlight greenhouse, and it creats a better environment for planting and breeding.keeps the biogas digester runing well in winter. 

Key words: courtyard ecosystem, ecological model, sunlight greenhouse, temperature raising and maintaining, biogas