Karen Reynolds told a dispatcher Dorner had tied her and her husband Jim, and left with their car keys, the Los Angeles Times reported. She said it had taken them as much as half an hour to get free and dial 911.
The tape was released Tuesday by authorities in San Bernardino County.
Dorner, a former Navy reservist fired from the Los Angeles Police Department after reporting another officer for brutality, went on a killing spree in February. He took his own life in a burning cabin in the San Bernardino mountains after being surrounded by police.
"We walked in on him and then he left," Karen Reynolds said in her call. "We came into this unit and he was in here. He got us blindfolded and put stuff in our mouths and put pillowcases on our heads and had us tied up."
She told the dispatcher Dorner might have been hiding in the condo near Big Bear for several days.
The couple have applied for a share in a $1 million reward posted for information leading to Dorner's capture. Los Angeles police have said a three-judge panel will decide how to deal with the reward.