Although insight in how adolescents' food intake is affected by the COVID-19 pandemic is critical, knowledge is limited. Hence, this longitudinal study (N = 691, M[subscript age] = 14.30, SD[subscript age] = 0.62; 52.5% female) investigated changes in adolescents' unhealthy (sugar-sweetened beverages, sweet snacks, savoury snacks) and healthy (fruit and vegetables) food intake (in total, obtained from home, and from outside the home) from pre-pandemic (Spring 2019) to the first lockdown (Spring 2020) and to six months later (Fall 2020). Moreover, several moderating factors were assessed. Results showed that the intake of unhealthy and healthy food in total and obtained from outside the home decreased during the lockdown. Six months later, unhealthy food intake returned to pre-pandemic levels, while healthy food intake remained lower. COVID-19 stressful life events and maternal food intake further qualified these longer-term changes in intake of sugar-sweetened beverages and fruit and vegetables, respectively. Future work is warranted to elucidate longer-term COVID-19 effects on adolescents' food intake.