The 31-year-old has been dating current boyfriend Alex Beh for the past eight months and said she definitely picks up a copy of her book The Day I Shot Cupid when she's after some romance advice.
She said to UsMagazine.com: 'Honestly, I know it's cheesy, but it's really helped me.'
The actress recently celebrated Valentine's Day with her boyfriend as well as her brother, sister-in-law and baby niece.
She told the US website that Beh gives her flowers 'every single day'.
Love Hewitt added: 'He'll either give me a bouquet, or handpick one.'