Tea Harvesting involves the removal of the tender, growing shoots from the surface of the tea bush. There are two processes that take place in tea harvesting. These include; coarse plucking and fine plucking. Fine plucking involves picking the bud and the second and third leaves while for the coarse plucking more leaves are picked with the bud. Quality deterioration is mainly due to mechanical injury and non-selective plucking with shear-harvesting. The use of machines increases the plucking average with a net decrease in cost of production compared to hand plucking. The adoption of mechanical harvesting machines translates to low quality of the harvested tea since the process is coarse and picks more unwanted leaves. Therefore, this study sought to find the factors affecting the adoption of mechanical tea harvesting methods (MTH) in Kenya with a specific reference to the west-rift region of Kenya. However, the specific objectives of the study were to find out whether the quality of tea leaves, cost of production, land size and farmers level of education affect the adoption of mechanical harvesting methods in the tea industry in Kenya. The study used descriptive research design to investigate the subjects by observing and describing their behavior without influencing them in any way. This study targeted a population of 349604 small holder tea farmers from the west rift region of Kenya. Questionnaires were used to collect quantitative data. The instruments of data collection were divided as per the variables and objectives to ensure that the content would be comprehensive and representative. The study used a sample size of 383 respondents from which 287 filled in and returned the questionnaires making a response rate of 74.93%. This formed a reliable response in the data collection. The completed questionnaires were verified, coded and analyzed using Statistical Package for the Social Sciences version 21. Data was presented using frequency tables, pie-charts and histograms. The study showed that quality of the harvested tea, cost of production, land size and the farmer‟s level of education are some of the factors that affect the adoption of mechanical tea harvesting. The study indicated that there is a positive linear relationship between quality of tea leaves, Land Size Farmer and the Education Level of the smallholder farmers and adoption of Mechanical tea harvesting methods (MTH). The study concluded that capacity building through training, good planting design, good road infrastructure to ease market and information access, better tea prices and support to access credit for the farmers are some of the ways which will encourage the farmers to adopt mechanical tea harvesting method. Tea production cost reduces with the introduction of machine harvesting and the Net Present Value of machine harvested tea is twice as much as the NPV of hand-picked tea.