The reality of noise pollution as a major threat to the environment is no longer questionable. Experts have said that its effect ranges from sleep disturbances, speech impairment, to other health and psychological challenges. Taking root from industrial activities, automobile, air traffic and household generator sets the environment suffers the aftermath of these continuous bombardments. Added to this is religious-oriented noise. This results from the daily activities of different religious groups in relation to their environment. The study examined the sources and effect of religious noise among the three major religions in Nigeria: Christianity, Islam, and African Traditional Religion using Ilishan-Remo as case study. Using stratified method of sampling, two hundred and forty copies of questionnaire were distributed to respondents from the three religions. The data elicited from the survey were analyzed using simple statistics of frequency of occurrence. We discovered that sources of religious noise in Ilishan-Remo included the use of ear-shattering loudspeakers by Christians and their Muslim counterparts during morning and night worship sessions; and the drum beats of adherents of African Traditional Religion during their festivals. The effect of such noise pollution included sleep disturbances, disruption of personal meditation and rest, speech disturbances, and the ability to aggravate high blood pressure among patients and potential victims, among others. Top on the list of possible solution to such practices include ban on the use of loud speakers in residential areas, location of churches in non-residential areas, and education of adherents of these religions on worship decorum and the need for environmental sustainability.