The report has been released by the Oxford Internet Institute, which focused on Nintendo's 'Animal Crossing' and EA's 'Plants vs Zombies', and asked the study participants about their experiences of the games.
Professor Andrew Przybylski, who led the study, said: "If you play 'Animal Crossing' for four hours a day, every single day, you're likely to say you feel significantly happier than someone who doesn't.
"That doesn't mean 'Animal Crossing' by itself makes you happy."
The academic explained that previous research suggested that the longer people play games, the more unhappy they become.
Professor Przybylski hinted that the social elements of the games might have made a crucial difference to the outcome of the study.
He said: "I don't think people plough a bunch of time into games with a social aspect unless they're happy about it."
Despite this, the expert admits that more research is needed.
He explained to the BBC: "We need to study more games, and more players, over more time. It would be like letting psychologists study all the playgrounds in the world.
"We might build a theory of bullying or learn how people build new friendships. My hope is that this fosters curiosity and collaboration and open data."