The Republic of Ireland captain joined the Major League Soccer side from Tottenham Hotspur in August and has gone on to score two goals for his new side.
"[Keane's] a great guy and great guys settle into any kind of set-up," Beckham told BBC Sport.
"He's scored goals, which he's always going to do, and he has settled in both off the pitch and on the pitch.
"It's great to have his ability in this team and he makes headlines. His goalscoring does that."
Keane, 31, is Ireland's all-time record goalscorer.