And inside jokes are particularly important because they 'affirm your relationship through laughter', the researchers claim.
But, they warn, couples who share 'mean-spirited jokes' are unlikely to last, with nasty jibes indicating a problem in the relationship.
The research was carried out by the University of Kansas and led by associate professor Jeffrey Hall from the department of communication studies.
'Playfulness between romantic partners is a crucial component in bonding and establishing relational security,' Professor Hall said.
'Particularly shared laughter, is an important indicator of romantic attraction between potential mates.'
The scientists analysed 39 studies made up of more than 150,000 participants to determine how important humour is in a romantic relationship.
Results - published in full in the next issue of the journal Personal Relationships - suggest that people thinking you are funny or can make a joke out of anything does not mean you will be more lucky in love.
But couples who 'create humour together' - via inside jokes - are more likely to last.
'People say they want a sense of humour in a mate, but that's a broad concept,' Professor Hall said.
'What is strongly related to relationship satisfaction is the humour that couples create together.
'Say you and your partner share a quirky sense of humour, but romantic comedies or sit-coms do nothing for either of you.
'It's not that any style or sense of humour is any better or worse. What matters is you both see quirky humour as hysterical.
'If you share a sense of what's funny, it affirms you and affirms your relationship through laughter.'
But before you laugh at your other half's receding hairline or moan about your mother-in-law, Professor Hall warns couples not to go too far.
'Having an aggressive sense of humour is a bad sign for the relationship in general, but it is worse if the style of humour is used in the relationship,' he said.
'If you think that your partner tells mean-spirited jokes, then it's likely you've seen that firsthand in your relationship.'
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