Youth is a period of transition associated with immense biological, physical, and social changes, which increases the vulnerability to mental illnesses. The study aimed to establish the prevalence of severe and extremely severe levels of depression and anxiety symptoms among the youths in Singapore and identify the psycho-social factors associated with them. The National Youth Mental Health Study was a cross-sectional epidemiological study of Singapore Residents aged 15-35 years. The youths self-administered the survey on tablets containing the programmed questionnaires. The Depression Anxiety Stress Scales Short Form (DASS-21) was used to assess youths' mental health. Multiple logistic regressions were conducted to examine the socio-demographic correlates and to identify factors associated with psychological distress. The prevalence of severe and extremely severe symptoms of depression was 14.9 % among youths in Singapore. Severe and extremely severe levels of depression symptoms were highest among those in the age group of 20-24 years (20.9 %). The prevalence of severe and extremely severe levels of anxiety symptoms among youths in Singapore was 27.0 %. The prevalence was significantly higher among females (28.9 %) than males (25.0 %). Severe and extremely severe symptoms of anxiety were highest among those in the age group of 20-24 years (34.1 %). Body shape concerns, daily smoking, and self-esteem were significantly associated with severe and extremely severe symptoms of depression and anxiety. The high prevalence of severe and extremely severe levels of depression and anxiety highlights the need for comprehensive and accessible mental health services tailored to the unique challenges faced by youths.