Background: Internet usage has been rapidly increasing among the general population in the modern era. India has been ranked fourth among highest number of internet users next to China, U.S and Japan. Even though the internet provides better opportunities for communication, information and social interaction, its excessive use leads to addictive behavior with mental health implications. Taking this into consideration we conducted a study to assess the prevalence and levels of internet addiction and to determine the behavior aspects among professional college students. Methods: A cross sectional study was conducted among 600 undergraduate students of medical, dental and nursing colleges from December 2017 to March 2018 by using population proportion to sample size and by stratified sampling technique. Internet addiction was analyzed using internet addiction test questionnaire. Result: Among 600 students, 94.8% males were more addicted to internet than females (83.4%). Internet addiction was present in 87.5% of students. BDS students (90%) were more addicted to internet than nursing and medical college students. Internet addiction between males and females were found to be statistically significant. About 70.8% of students used internet for social networking. 58.8% of students had mild level of internet addiction and only 1.5% students had severe level of internet addiction. Among those who were addicted to internet, females had decreased outdoor activity due to internet usage, had felt sleeplessness due to late night log in and were depressed when offline. Conclusion: Internet usage has been increased among the professional college students which will also affect the physical and mental health. An awareness regarding the internet use and opportunities for recreational activities should also be created.