Objective: To assess the three-dimensional vision syndrome among the viewers of three-dimensional movies. Methods: This cross-sectional study was conducted at the Ziauddin University, Karachi, from July to November 2015 among viewers of three-dimensional movies. The frequency of three-dimensional vision syndrome during and at the end of a movie was assessed. A self-administered questionnaire was used to collect data immediately at the end of the movie. Data was analysed using SPSS 20. Results: There were 474 participants with an overall mean age of 25.6 +/- 10.1 years; 270(57%) participants were male and 204(43%) were female. Most common symptoms were tired eyes, blurred vision and headache found during the movie among 96(20.3%), 73(15.4%) and 43(9.1%) individuals, whereas at the end of the movie among 100(21.1%), 33(7.0%) and 35(7.4%) viewers, respectively. Movies with duration of 2 to 3 hours were also more likely to be associated with three-dimensional vision syndrome during and at the end of the movie (p= 0.001) and (p= 0.004). Conclusion: Watching three-dimensional movies increased the likelihood of visual fatigue and visually-induced motion sickness.