Care typess is considered the cornerstone of orphan's happiness and health. In 2022, China had more than 190,000 orphans in different types of care. The purpose of the study is to examine the relationship between care types and development of orphans in China. We conducted an empirical study using cross-sectional survey data related to orphans from LZ City, Sichuan Province, China, in 2020. The data sample consists of 320 valid samples of orphans and their families, including 166 boys and 154 girls. The study conducted multiple linear regression model to analyze the relationship between care types and other family variables and the development of orphans. The results indicate that compared with other care types, grandparent care has a significant positive impact on the overall development and psychological status of orphans, with this impact being moderated by the social participation of guardians. The higher the social participation of guardians, the greater the positive impact of grandparent care on the development of orphans. Further analysis, grouped by sex and age, revealed that the effects of care types on orphan development are influenced by the gender and age of orphans. Specifically, girls and younger orphans tend to exhibit better development in a grandparent care family. The research results of this study provide an empirical basis for the government to formulate policies, and for the government, society and family to jointly ensure the better development of orphans.