Objective: To understand the characteristics of injury cases in Longhua District, Shenzhen City, Guangdong Province from 2021 to 2024, so as to provide the evidence for the development of injury prevention and control measures. Methods: The data of injury cases in the first visit due to injury in the sentinel hospitals of Longhua District from 2021 to 2024 were collected from the Shenzhen Injury Surveillance System. The time, cause, place, activity, intention, nature, position, severity, and outcome of injury were described. Results: From 2021 to 2024, a total of 167 524 injury cases were reported in Longhua District, with a male-to-female ratio of 1.89∶1. The incidence of injuries was higher in cases aged 30-<45 years (49 957 cases, 29.82%). Injuries mainly occurred from July to August (31 272 cases, 18.67%). The main cause of injury was falls (52 048 cases, 31.07%). Injuries mainly occurred at home (64 110 cases, 38.27%). Leisure activities were the main activities when injuries occurred (79 008 cases, 47.16%). Most of the injuries were unintentional (159 173 cases, 95.02%). The main type of injury was contusion/abrasion (71 900 cases, 42.92%). The main injury site was upper limb (64 247 cases, 38.35%). Most injuries were mild (131 369 cases, 78.42%). The main injury outcome was discharge after treatment, 160 882 cases (96.04%). The second cause of male injury was blunt force injury (30 140 cases, 27.49%), and the second cause of female injury was animal injury (14 648 cases, 25.31%). Fall was the leading cause of injury in people aged 0-<15 years and ≥65 years, and blunt force injury was the leading cause of injury in people aged 15-<65 years. The second place for male injuries was industrial and construction places (23 722 cases, 21.64%), and for female injuries was school/public places (9 644 cases, 16.66%). The first place for injuries in people aged 45-<65 years was in industrial and construction places. The proportions of fractures, moderate injuries, and hospitalizations increased with age (all P<0.05). Conclusions The main injury cases in Longhua District were males and people aged 30-<45 years. July and August were a period of high risk for injuries. People aged 0-<15 years and ≥65 years were the high-risk groups of falls. More attention should be paid to the fracture risk in the elderly.