The study examined the effect of trade union activities on employee job satisfaction in the health sector in Mbale City, Uganda. The specific objectives were; i) to analyze the effect of lobbying for attractive pay on job satisfaction of workers in the health sector in Mbale City; ii) to determine the effect of advocating for conducive work conditions on job satisfaction of workers in the health sector in Mbale City; and iii) to establish the effect of advocating for acceptable non-financial compensation schemes on job satisfaction of workers in the health sector in Mbale City. A cross-sectional design was used alongside quantitative and qualitative approaches whereby questionnaires and interviews were employed to collect data from 93 respondents out of the 112 targeted, giving a response rate of 83%. Purposive and simple random sampling techniques were used to select union leaders, doctors, clinical officers, nurses and midwives. The results were analyzed using frequencies, percentages, correlation and regression analysis. The findings revealed that; a) lobbying for attractive pay had a positive and significant effect on job satisfaction (β = .254, t = 2.177, p = .032); b) advocating for acceptable non-financial compensation schemes had a positive and significant effect on job satisfaction (β = .451, t = 4.632, p < .001); and c) advocating for conducive work conditions had a positive but insignificant effect on job satisfaction (β = .124, t = 1.061, p = .292). The study concludes that attractive pay and acceptable non-financial compensation schemes have a greater influence on employee job satisfaction than conducive work conditions. The study recommends that health-sector management and trade unions strengthen mechanisms for negotiating attractive pay and non-financial benefits while improving working conditions to enhance employee job satisfaction and service delivery.