This paper examined on-the-Job Learning as a Catalyst for Improved Employee Performance in Devolved Government Systems. A Case Study of County Government of Murang’a, Kenya. A descriptive research design was used, targeting 1,022 managementlevel employees. A sample of 287 respondents was selected using stratified random sampling, and data were collected through structured questionnaires. Descriptive statistics and inferential analyses were conducted using SPSS (Version 25). The results indicated that on-the-job learning significantly enhanced employee performance, with an overall composite mean of 3.64. Employees reported that on-the-job learning improved proactive communication (M = 4.46, SD = 0.92), skill utilization (M = 4.37, SD = 0.95), and problem-solving ability (M = 4.26, SD = 1.00). Correlation analysis showed a positive relationship between on-the-job learning and performance (r = 0.543, p < 0.01), while regression results revealed that on-the-job learning explained 29% of the variance in employee performance. The study concludes that structured on-the-job learning fosters adaptability, innovation, and efficiency in devolved government systems. It recommends institutionalizing workplace learning through formal programs, reflection workshops, and feedback mechanisms to enhance public sector service delivery. Future research should adopt longitudinal and comparative designs to assess the sustainability of on-thejob learning outcomes across counties and sectors