Informal sectors in urban areas of Kenya play a significant role in the economy, yet their workers often face challenges related to psychological well-being. A cross-sectional survey was conducted in Nairobi, employing a convenience sampling method. A structured questionnaire was distributed to 500 randomly selected participants from various sectors within the city’s informal economy. Survey results indicated that approximately 60% of respondents reported experiencing high levels of job-related stress, with women more likely to report higher stress levels compared to men. The study highlights significant disparities in psychological health outcomes among urban Kenyan workers from the informal sector and underscores the need for targeted interventions. Policy makers should prioritise initiatives aimed at improving working conditions and mental health support services specifically for urban informally employed populations.