The Secret to Happiness Is Love (我愛你 x4) is a studio album by Taiwanese artist Vivian Hsu.

The original title Wǒ Ài Nǐ means "I Love You".

There were three versions of this album produced: a limited edition with artbook, a preorder edition with artbook and bonus single CD, and a regular edition without the artbook, but with a VCD containing music videos.

The album contains Hsu's first rap song, Mianju, which was later featured in the compilation album Ji Le 175.

Also featured is Jueding Ai Ni (決定愛你; Juédìng Ài Nǐ), the theme song to the TV series Love Storm, in which Hsu starred in.