Speaking with former Dallas Cowboys wide receiver Michael Irvin, who originates a nationwide talk show from Dallas, Howard said he was not alone.
"Everybody in the media world and the sports world knows NBA players do smoke marijuana," Howard said. "Most of the players in the league use marijuana and I have and do partake in smoking weed in the offseason sometimes.
"I mean, that's my personal choice and my personal opinion, but I don't think that's stopping me from doing my job."
The Mavericks went into Friday's playoff game against New Orleans facing a 2-0 deficit in the best-of-seven quarterfinal series.
Howard has been criticized for his performance early in the series, having averaged 13.5 points per game while making just 26 percent of his shots from the field.
Under the NBA's drug policy, players have to undergo four random tests every season. A player who tests positive for marijuana use is not subject to suspension until a third strike.