The 32-year-old became a fan of US TV show The Bachelorette and was confused when runner-up Ben, a winemaker from Sonoma, California, was rejected by Ashley Hebert in favour of JP Rosenbaum.
She tweeted: 'OMG! Ben F...Gotta book a flight to Sonoma!!!'
And, according to Life & Style magazine, she wasn't joking - Jennifer and Ben were reportedly spotted dining out in San Francisco, California, on Saturday.
The pair were seen at the Lion's Pub, where revellers told the publication they were 'making out'.
Another onlooker added: 'Ben and Jennifer Love Hewitt appeared to be dating.'
The Hollywood star has had a string of romance let downs recently including her split from Alex Beh in May, after less than a year of dating.