Background <p>Modern contraceptive use among adolescent girls and young women (AGYW) is an effective strategy for preventing early and unintended pregnancies, which contribute to various social, economic, and health challenges in low- and middle-income countries, including Tanzania. We investigated the prevalence and predictors of modern contraceptive use among AGYW in Tanzania.</p> Methods <p>An analytical cross-sectional survey was conducted using the 2022 Tanzania Demographic and Health Survey data, and multistage stratified sampling was used to recruit participants across the country. Given the complex survey design, a weighted multivariable logistic regression was used determine the predictors of modern contraceptive use. Adjusted odds ratio (aOR) with corresponding 95% Confidence Intervals (CI) were computed to estimate the strength of association between independent variables and modern contraceptive use. All analyses were performed using Stata version 18.5.</p> Results <p>The prevalence of modern contraceptive use was 28.4% (95%CI: 26.2- 30.7). AGYW in primary education (aOR = 1.85, 95%CI: 1.23–2.69), secondary education (aOR = 1.99, 95%CI: 1.39–2.95), having 1–2 children (aOR = 4.34, 95%CI: 3.15–5.98), working (aOR = 1.33, 95%CI: 1.07–1.66), those visited the health facility in the past 12 months (aOR = 1.42, 95%CI: 1.14–1.76) and AGYW in richest quantile (aOR = 1.82, 95%CI: 1.26–2.62) were more likely to use modern contraceptive. Conversely, AGYW aged 15–19 years (aOR = 0.72, 95%CI: 0.56–0.91), in the western region (aOR = 0.48, 95%CI: 0.28–0.82) and those living in Zanzibar (aOR = 0.47, 95%CI: 0.28–0.80) were less likely to use modern contraceptives.</p> Conclusion <p>Nearly three in ten AGYW used modern contraceptives. The use of modern contraceptives was associated with various factors. Establishing specific interventions to improve coverage and uptake of modern contraceptives could help to address inequalities in modern contraceptive use among AGYW in Tanzania. </p>