Peter Madsen, 47, is accused of killing 30-year-old Kim Wall in August 2017.
The freelance journalist never returned after going to interview him on the submarine. Days later, her dismembered body was found in the sea.
Madsen admits dismembering Ms Wall’s body and throwing it overboard, but denies a charge of premeditated murder.
At the trial at Copenhagen City Court, prosecutors said police found 41 images of hanged girls, and other violent content featuring the murders of women and some men.
They also found searches from 2011 using keywords such as “beheadings real”, “stabby stabby” and “suicide videos”.
Detectives uncovered other searches which led to material called “Mexican female beheading”, “female beheading in Mexico” as well as “woman in agony while being slowly beheaded with small knife”.
The court heard police discovered more material on computers from Madsen’s lab, including animated films containing the decapitation of naked women, naked men being impaled and a woman being burnt at the stake.
The prosecution showed the court some of the pictures of hanged women, as well as images and text about impaling.
Detectives also examined his mobile phone and found several searches for violent content made on numerous occasions.
Earlier, the court heard from a female witness who cannot be named.
Questioned by the defence, the witness said she had never visited Madsen’s submarine even though she wanted to and they had discussed her taking pictures of it.
She told the court: “I perceive him as very sex fixated. That was what we talked about when we met by chance. Other than that, a special person.”
Asked whether she found him violent, she said: “No.”
The 12-day trial will continue for its 10th day on Thursday.