Orange County Fire Authority Capt. Larry Kurtz said two adults and two children were displaced from the home when the blaze broke out at about 6:15 p.m. in the 6600 block of Kameha Circle.
The OCFA tweeted that 32 firefighters battled the residential structure fire and got control of the blaze, which spread to the duplex's attic. It was put out in about 30 minutes.
Two dogs were pronounced dead at the scene, fire officials said. The pets, along with the displaced victims, were from the duplex's left-side unit.
The cause of the fire was under investigation.
The American Red Cross was assisting the displaced residents, Kurtz said.
City News Service contributed to this report.