Objective To understand the prevalence of residents insect bite dermatitis in Laizhou urban area in order to improve control measures. Methods The residents outdoors were selected and diagnosed with insect bite dermatitis or not by dermatologists in five sampling sites. Key information of gender, age, the number and distribution of rashes were collected and analyzed. Results The prevalence of insect bite dermatitis was 36.63%, and the residents over 41 years old had higher prevalence than underage ones (χ²=86.640, P< 0.01), and there was no difference between males and females (χ²=1.500, P=0.220). The cases with the number of rashes less than 10 accounted for 96.46%, and no significant difference of skin lesions in gender and age. The cases with rashes only distributed in the lower extremities accounted for 79.02%, and women's upper arms had more probability to be bitten compared with men's, while the elder people had less probability in contrast to younger ones. Conclusion The prevalence of insect bite dermatitis in Laizhou urban area is high, and the control measures and health education work should be strengthened.