Gangs are apparently not a new occurrence, but they are still a problem that has to be addressed. Youth gangs have become one of the most serious crime problems in most of the developed countries as well as countries such as Sri Lanka. Gang violence and behavior including substance use, homicides and assaults, drive-by shootings and brutal home-invasion robberies--accounts for one of the largest, single, personal threats to public safety. There is a great deal of variability in gangs, gang activity, and gang problems. Gangs vary by ethnic makeup, involvement in predatory crime, drug-related activities, and age of members, propensity toward violence, and organizational stability and unity. Even for a single factor such as drug trafficking, there is variation among gangs in the types of drugs sold, the aggressiveness used in expanding drug markets, and the willingness to use violence. These variations exist within and among different communities. This study seek to identify Drug abuse among youth gangs and its social impacts in Colombo city. 493 youth were identified (age range 18-32) 4 through snowball sampling and data gathered from questioners, observations, interviews and case studies. Findings said their drug related subcultural characteristics and how those impact to the society.