Background: One of the most important parameters that affect the development of adolescents is nutrition. Eating practices among adolescents may have long-term impact on their health, Aims: This study aimed to assess whether there is a difference in food intake and physical activity patterns among male and female adolescents (12-19 years old) in the Gaza Strip. Methods: The cross-sectional study was conducted in April 2016 among 378 adolescent students, 205 males, 173 females. Researchers utilized quantitative and qualitative measures by incorporating a face-to-face interview questionnaire with the adolescents and focus group discussions with parents. Results: Over 55% of participants were eating healthy foods with high frequency; the proportion of boys was greater than that of girls (P < 0.05). Around 45% were eating unhealthy foods with high frequency; here the proportion of girls was greater, but the difference was not statistically significant (P > 0.05). In terms of physical activity pattern, more than half of the adolescents were practicing a sedentary lifestyle, girls statistically significantly more than boys (P < 0.001). No statistically significant sex-based association was found between food intake habits and physical activity pattern. Conclusions: Palestinian adolescents of both sexes in the Gaza Strip are practising unhealthy feeding habits coupled with an apparently highly sedentary lifestyle.