They raided an apartment near Central Avenue and North Sharon Amity Road. Police said they and federal agents had been working the case for a year.
Investigators said they had reason to believe there was so much heroin in the apartment that they wanted to move on it before it got out on the street.
Police said they found 8 pounds of black tar heroin, which has a street value of $500,000.
"If you break it down, (that's) 36,000 individual injections of heroin," one undercover officer said. "That's what that really boils down to."
Officers said no one was home at the time, so no arrests were made.
In June, police said Charlotte is one of the five-worst U.S. cities for black tar heroin use.
More Information: CMPD Crime Mapping
Previous Stories: June 28, 2011: CMPD Says It's Pushing Resources Toward Black Tar Heroin Issue June 28, 2011: Charlotte No. 5 In Top US Cities For Black Tar Heroin April 20, 2011: Police Discover $100K In Black Tar Heroin In Charlotte Home July 27, 2010: 9 Investigates: Eyewitness News Takes You Inside The Black Tar Heroin Trade