Background and Objective: Individuals habit has been changed due to technology improvement as a result fast food consumption has dramatically increased in Iran. This study was done to determine the effective factors on Fast food consumption among high-school students based on planned behavior theory.

Methods: This descriptive-analytic, cross-sectional study was conducted on 500 high-school students in Aliabad city in Golestan province in north of Iran in one year study from October 2014-2015. A valid and reliable researcher-made and self-administered questionnaire based on TPB constructs (including attitude, subjective norms, perceived behavioral control and behavior intention) was utilized to collect the data.

Results: The frequency of fast food consumption was 4.01 per month and hamburger and pizza were the most prevalent fast foods. TPB explained fast food consumption behaviors with relatively high R2 around 0.65, effectively. Frequency of fast food consumption was significantly associated with behavioral intention and subjective norms (P<0.05).

Conclusion: As friends are the effective subjective norm for student fast food consumption therefore, they must specifically be considered in developing beneficial educational interventions.