Since the beginning of the COVID-19 pandemic, an increase in pornography use has been reported based on cross-sectional findings, raising concerns about associated adverse outcomes, such as problematic pornography use (PPU). The aims of the present study were to document potential changes in adolescents' pornography use frequency, motivations, and PPU before and during the COVID-19 pandemic. As part of an ongoing study on adolescents' sexual health, we used a large sample (N Time 1 = 1771; 47.6% girls, M age = 15.42 years, SD = 0.59) to examine changes from baseline (before the COVID-19 pandemic) to one year later (during the COVID-19 pandemic) in adolescents' self-reported pornography use frequency, motivations, and PPU, using latent change models and examining potential gender differences. No significant changes were observed in adolescents' pornography use frequency and pornography use motivations, and no gender differences were present in these trends. Although statistically significant, slight decrease was observed in boys' PPU levels, and a statistically significant, slight increase was observed in girls' PPU levels, these changes were very small, providing no practical or clinical relevance. In sum, despite previous propositions, concerns, and cross-sectional findings, longitudinal results suggest that adolescents' pornography use characteristics were rather stable between November 2019 and June 2021, and the COVID-19 pandemic and related lockdowns might not have led to general increases in adolescents' pornography use as it was expected.