This study explores the revenue and operation cost structures of private kindergartens in China as profitability is key to their sustainable development. Altogether 233 private kindergartens were sampled and involved in the survey study, which provides a quantitative analysis of the researcher-designed Questionnaire on the Revenue and Cost of Private Kindergartens (QRCPK). And 23 of these participating kindergartens were involved in a semi-structured interview. Analyses of both survey and interview data jointly indicated that: (1) the majority of the revenue of private kindergartens depended on the tuition fees; (2) their labor cost and rent costs are massive high; (3) the low profitability has been proved by the high cost-revenue ratio; (4) the poor cost accounting and financial management strategies hindered the sustainable development of private kindergartens.