The last decade has witnessed a sky rocketing increase in alcohol and drug use, where it is estimated that 39.5 million people have substance use disorders (UNODC, 2023). It is opined that religion in the lives of youth can mitigate against alcohol and substance use, but research indicates that in spite of the religious beliefs, there is still a significant proportion of youth in churches who are involved in alcohol and substance use (National Study of Youth & Religion, 2024). Christian youth grappling with alcohol and drug use are caught in between following that which is biblically acceptable versus the societal norms and culture (Swindell, 2010). Thus, investigating the prevalence of alcohol and substance use among Christian youth, is crucial to pinpointing the causative factors and developing targeted programs. The purpose of this study was to evaluate the prevalence of alcohol/ substance use among Christian youth in four selected churches in Kajiado County, Kenya. It employed a descriptive research design with a sample size of 145 youth (14-35 years;73 male,72 female), who were actively attending Sunday services in the four churches. Data collection utilized the Alcohol, Smoking and Substance Involvement Screening Test- ASSIST- LITE and a socio demographics questionnaire. The data was analyzed quantitatively in SPSS using frequencies and percentages. Findings from the socio demographic questionnaire inquiring on whether respondents ‘had ever used alcohol/substances’ showed that 53(36.6%) of the respondents affirmed that they had ever used alcohol, 12(8.3%) both khat and alcohol, 3(2.1%) khat, hash and alcohol while 5(3.4%) had ever used other substances and alcohol. The ASSIT-Lite inquired on alcohol and drug use in the past three months, where the most frequently used was alcohol at n=42(28.9%), then cannabis at n=27(18.6%), sedatives at n=14(9.7%), stimulants at n=10(6.9%), psychoactive substances at n=6(4.1%) and then opioids at n=3(2.1%). Of the alcohol/substance users, 12(8.3%), 7(4.8%) and 5(3.4%) were at high risk levels for alcohol, cannabis and stimulant use respectively. The study was informative in that, it revealed Christian youth were still grappling with alcohol/substance use, and hence, targeted psychological and behavioral interventions, alongside the church-based programs are necessary.