Health-risk assessments of temperature are central to determine total non-accidental human mortality; however, few studies have investigated the effect of temperature on accidental human mortality. We performed a time-series study combined with a distributed lag non-linear model (DLNM) to quantify the non-linear and delayed effects of daily mean temperature on accidental human mortality between 2013 and 2017 in Shenzhen, China. The threshold for effects of temperature on accidental human mortality occurred between 5.6 °C and 18.5 °C. Cold exposures, but not hot exposures, were significantly associated with accidental human mortality. All of the observed groups were susceptible to cold effects, with the strongest effects presented in females (relative risk [RR]: 3.14, 95% confidence interval (CI) [1.44-6.84]), followed by poorly educated people (RR: 2.63, 95% CI [1.59-4.36]), males (RR: 1.79, 95% CI [1.10-2.92]), and well-educated people (RR: 1.20, 95% CI [0.58-2.51]). Pooled estimates for cold effects at a lag of 0-21 days (d) were also stronger than hot effects at a lag of 0-2 d. Our results indicate that low temperatures increased the risk of accidental human mortality. Females and poorly educated people were more susceptible to the low temperatures. These findings imply that interventions which target vulnerable populations during cold days should be developed to reduce accidental human mortality risk. Along with the climate change, the effect of temperature on human mortality remains an issue of increasing public health significance worldwide 1. The considerable temperature impact on human mortality have been extensively reported in many countries at global. For example, a global study including 306 communities across twelve countries /regions with varies climate patterns revealed both cold and hot temperatures increased the risk of non-accidental human mortality 2. A national study of mortality including 12 large cities in China found that 1 °C increase of moderately high temperature is associated with 4.6%, 4.2%, and 6.3% in mortality of non-accidental cause, circulatory disease and respiratory disease, respectively 3. The proportion of temperature-related stroke death was 17.7% in southern China 4. These findings highlight the adverse effects of temperature on non-accidental human mortality. However, most of previous studies on this subject have been focus on examining the effects of temperature on non-accidental human mortality and cause-specific human mortality, few studies have quantified the effects of temperature on accidental human mortality, especially in China, despite growing awareness of human vulnerability to weather change. Accidental human mortality was characterized by unexpected causes, and unintentional events or behavior, including transport accidents and other external causes of accidental injury, such as falls, accidental drowning and submersion, accidental poisoning. It is a well-recognized major cause of death and contributes significantly to health care costs and the burden on society...