Construction projects in China are subject to multiple safety production supervision and liability systems strictly enforced by central or local governments. Such a strong supervision system in practice seems to have limitations in preventing falling accidents that cause life and property losses. Many research studies focused on falling from height (FFH) and put forward many countermeasures, but many safety supervision problems remain. Some example questions are (1) why are the regulatory mechanisms ineffective? and (2) what are the hidden factors that trigger failures of preventing falling accidents? The authors collected 118 official falling accident reports from governmental websites and extracted accident causes from the reports. Based on HFACS (human factor analysis and classification system) and "24 Model" developed in previous studies, the authors proposed an analytical framework for safety supervision assessment and classified accidental causes using the framework. With the data of the reports, the authors completed relative frequency analysis and Chi-square test between the causes of accidents. The authors identified factors that highly correlated with accidents. The main findings include (1) FFH is still the top accident type in terms of frequency and casualties in housing and municipal construction projects in China, (2) "safety devices are not used" is the top-1 cause for FFH, (3) "violation of discipline and directions," "risky operation," and "incorrect use of safety devices" which are related to workers behaviors are not influenced significantly by supervision, and (4) supervision company' safety management has no significant influences on unsafe supervision behaviors related to construction company except "safety education is not in place.".