This study was on the influence of Islam on Igembe people of Meru County. The research was driven by the slow and evolving importance of Somali Muslims in the activities of miraa business in the Igembe. The study was guided by objective: the influence of Islam on Igembe people of Meru County. The study employed Islamization theory by Bunger (1972) and immigration theory by Lee (1966). The combination of the two theories was the best to explain the influence of Islam on Igembe people. Descriptive research design was used and data collected using questionnaires and interview schedules. Stratified sampling technique was used to draw a sample size of 383 participants from the target population of 126,000 miraa farmers, miraa vendors and miraa traders’ association officials. Qualitative datasets were analysed by NVIVO and quantitative was analysed using SPSS version 22.0. The study findings revealed that Islam has pervaded Meru region and particularly spread among the Igembe people with significant impact being noticed as a result of their presence and influence. The study established that trade has played a significant role on the presence of Islam in Igembe region. The study established that there is both positive and negative influences on Igembe people by the presence of Islam religion. The study recommends guidelinesto eradicate negative influence as Islam religion interacts with the life, culture, and traditions of Igembe people.