Background: Waterpipe smoking is a growing public health threat worldwide. The aim of this study was to assess waterpipe smoking prevalence and its associated factors among Iranian adults.Methods: This cross-sectional study was conducted in Kerman, Iran, recruiting 1090 adult participants using multistage sampling in 2016. A self-reported researcher-designed questionnaire was used. The socio-demographic characteristics and waterpipe smoking behaviors such as pattern, duration, and the most common place of waterpipe use, the type of tobacco, and the concurrent use of alcohol and substances were assessed. Data analyses were performed using chi-square, independent t-test, and multiple logistic regression.Findings: The prevalence of ever, current and daily waterpipe smoking were 43.8%, 28.8%, and 7.2%, respectively. Men initiated to use waterpipe in more early ages than women (P < 0.001). Café or restaurant (34.4%) and friends' house (36.8%) were the most frequent places for waterpipe using by men and women, respectively. Men used waterpipe 2.8 times more frequently than women. Waterpipe smoking was 4.9 times more likely in the 18-24 years age range compared to the 45 years or older. Waterpipe use was 2.4 times greater in the unemployed than in housewives. People with a university education were 1.4 and 1.7 times more likely to use waterpipe compared to people with high school diploma and illiterates, respectively.Conclusion: The present study revealed that men, high level of education, younger age and unemployment were associated with waterpipe smoking. Therefore, we need to design and implement more effective interventions, especially for vulnerable target groups.