I Cain't Say No is a song from the musical play Oklahoma! written by composer Richard Rodgers and lyricist/librettist Oscar Hammerstein II.

In the song, the secondary character Ado Annie Carnes describes her sexual awakening and the conflicts that it brings. Ado Annie has two principal suitors, a Persian traveling salesman Ali Hakim, and the cowboy Will Parker, recently returned from an excursion to Kansas City. She describes to Laurey the attention she is now receiving from men "since she filled out" and her inability to say "no" to their advances.

Sample Lyrics

It ain't so much a question of not knowing what to do. I knowed what's right and wrong since I was ten. I heared a lot of stories and I reckon they are true About how girls're put upon by men. I know I mustn't fall into the pit, But when I'm with a feller, I forget! (fergit)

I'm just a girl who can't say no, I'm in a terrible fix I always say "come on, let's go" Jist when I orta say nix!