The drop in revenue came as two of Viacom's rivals, Time Warner Inc
Viacom's domestic advertising growth is very impressive, said RBC Capital Markets analyst David Bank. It just looks slightly less impressive coming after Time Warner and News Corp results.
Viacom's revenue fell to $3.83 billion, missing analysts' average forecast of $4.07 billion, according to Thomson Reuters I/B/E/S.
At the company's media networks division, which includes cable networks MTV, Comedy Central and Nickelodeon, first-quarter revenue rose 6 percent to $2.38 billion due mainly to stronger advertising sales, up 10 percent in the U.S.
Revenue at the filmed entertainment group, which includes Paramount Pictures, fell 16 percent to $1.5 billion on a 44 percent slump in home entertainment revenues.
Adjusted earnings per share of $1.02 beat analysts' average forecast of $1.00.
During the first quarter, net income from continuing operations was $629 million, or $1.02 per share, compared to $691 million, or $1.19 cents per share, a year earlier.
Shares were down $1.35 at $42.62 in premarket trading.
(Reporting by Jennifer Saba; Editing by Derek Caney)