Background: Smoking habit is a significant issue among university students. Little data available about smoking habit among Jordanian students. Aim: This study compared the levels of knowledge and attitude between smoker and nonsmoker university students in Jordan. Methods: A descriptive comparative cross-sectional approach was utilized. Data was collected from 300 students from four Jordanian universities via a self-report questionnaire. Data collection occurred during the first semester of 2024/2025 academic year. Results: The total knowledge scores for the smokers ranged from 0 to 208 (M = 151.07; SD = 33.3). The total knowledge scores for the nonsmokers ranged from 19 to 200 (M = 147.9; SD = 31.22). The smoker participants have total attitude scores ranged from 0 to 82 (M = 46.60; SD = 18.87). The total knowledge scores for the nonsmoker participants ranged from 0 to 65 (M = 26.60; SD = 13.41). The smokers have statistically higher knowledge scores across the three subscales—factors related to cigarette smoking initiation (t= 2.12, P = 0.04), factors related to hookah smoking initiation (t= 2.03, P = 0.04), and cigarette/smoking ban (t= 3.27, P = 0.001) subscales. Moreover, the finding that smokers have significantly higher mean scores on the total attitude scale and its subscales (p < 0.05). Conclusion: This study highlights significant differences in knowledge and attitudes toward smoking between smoker and non-smoker partcipants. Implications for nursing: nurses play a critical role in developing and implementing tailored educational interventions that address specific needs of smoker and nonsmoker university students.