Background <p>Anxiety disorders have a significant impact on youth globally; however, data from low- and middle-income countries such as Kenya are scant. This study aimed to determine the frequency and patterns of anxiety symptoms among Kenyan youth, as well as assess the relationships between anxiety symptoms and sociodemographic, economic, and comorbid mental health factors.</p> Methods <p>This was a cross-sectional study conducted in urban and peri-urban locations in the Nairobi Metropolitan area among 1,972 participants aged 14–25 years. The study used validated instruments, including the Anxiety Symptoms Questionnaire (ASQ), Beck Depression Inventory, and WHO-ASSIST. Descriptive statistics, t-tests, ANOVA, and Pearson correlations were used for statistical analysis, and a univariate GLM was used to determine the predictors of the anxiety symptoms.</p> Results <p>Anxiety symptoms were common, with the most reported cognitive symptoms being worry and nervousness. Females and participants from urban areas had significantly higher anxiety scores (<i>p</i> &lt; 0.001), with mean differences ranging from 6 to 15 points across frequency, intensity, and total scores compared to males and peri-urban participants. Anxiety scores had a negative correlation (<i>p</i> &lt; 0.01) with lower wealth index and moderate positive correlations with psychosis and bipolar disorder. Depression (<i>r</i> = 0.51; <i>p</i> &lt; 0.01), PTSD, and substance use (i.e., alcohol and cannabis) were comorbid conditions.</p> Conclusions <p>The study unearths the complexity of anxiety among Kenyan youth, with a nexus of social, economic, and psychological factors involved. These findings call for comprehensive mental health strategies focusing on reducing socioeconomic disparities and addressing comorbid conditions. Longitudinal trends and the efficacy of such interventions should be explored in future research for similar populations.</p> Clinical trial number <p>Not applicable.</p>