Substance abuse is an important health problem throughout the world including India, but prevalence and pattern of abuse varies from country to country and in different types of population. Slums have their own social and economic problems so that substance abuse may be different in this population and might be related with these problems. The aim of the present study was to study the prevalence and pattern substances in slum population. Prakash Chandra Sethi Nagar slum area of Indore district was selected for the purpose of this study. In first phase of the study, first a camp was organized to sensitize local leaders, key persons, and local inhabitants about drug abuse at Chandra Prakash Sethi Nagar. After that basic information was gathered with the key persons in Chandra Prakash Sethi Nagar. In second phase by house-to-house survey, all members of the family were interviewed in detail and information was recorded on semi-structured proforma. We observed prevalence rate of 560/1000 populations, 78.2% were males, 28.2% were females, and two-third abusers were laborers (72%). In order of frequency, tobacco was the most common substance abused in 53.9% population followed by gutka (nontobacco pan masala). Other drugs in order of frequency were alcohol 46.5%, cannabis 8.9%, opiates 4.9%, sedative and hypnotic 2.0%, solvents 1.0%, and cocaine in 0.1%. Slum population has higher prevalence rates than general population.