Disasters have become a typical occurrences all around the globe. Certainly, their frequency has grown as economic growth, technological sophistication, and vulnerability to disadvantaged groups has risen. Natural calamities are predicted to cause the deaths of one million people worldwide per decade. There is minimal evidence that M&E of disaster response operations leads to better results in terms of more effective practice. As such, the aim of this research will be to determine the influence of monitoring and evaluation capacity building on sustainability of disaster emergency preparedness program in Uasin Gishu County. This study adopted theory of Sustainability. This study used an explanatory research design. Because of the limited number of workers, a census survey will be used; this research target population will be 52 workers of the Disaster Emergency Preparedness Program and M&E in Uasin Gishu County. Questionnaires was used to collect data. Data analysis process will begin with questionnaire editing. Collected data were coded into Statistical package for social science (SPSS) for analysis. Descriptive statistics such as frequency distribution, percentages, means and standard deviations were calculated, and data presented in form of tables. Inferential statistics used were regression model. The study findings revealed that M&E capacity building has a positive and significant effect on Sustainability of disaster emergency preparedness programs (β1=0.885, p=0.000<0.05). The study concluded that Disasters and emergencies impact population health, and their consequences can be mitigated by planning, exercises, and preparedness. Monitoring and evaluation are essential for the sustainability of projects, including disaster emergency preparedness programs. Therefore, it can be concluded that monitoring and evaluation have a positive influence on the sustainability of projects. It can help in preventing, preparing for, respond to, and recover from humanitarian emergencies and large outbreaks. The study recommends that there is need for establishment of coordinating mechanisms, planning, financing, and implementing strategies to ensure the program’s sustainability. Developing a monitoring and evaluation framework that includes clear indicators to measure the program’s effectiveness and sustainability.