Community-Based Gang Intervention Act - Expresses the sense of Congress that the United States should acknowledge and address social conditions such as poverty, homelessness, inadequate educational systems, and limited economic opportunities in developing a comprehensive gang violence reduction strategy.

Amends the Juvenile Justice and Delinquency Prevention Act of 1974 to: (1) require the Administrator of the Office of Juvenile Justice and Delinquency Prevention to award grants to nonprofit community-based gang intervention agencies to provide services for reducing and stopping gang-related and gang-motivated violence and crime, (2) include representatives of community-based gang intervention agencies in juvenile justice and delinquency prevention advisory groups established by state plans, and (3) include community-based gang intervention and prevention activities in state and local grant programs for delinquency prevention.