World 3-S

World 3-S or World 3-Secret may refer to:
 * Go! Go! Morphing!, World 3-S in Yoshi's Island: Super Mario Advance 3.
 * A Light in the Dark, World 3-S in Yoshi's Island DS.
 * Ride the Blarggwich, World 3-S in Yoshi's New Island.
 * Woollet Bill's Last Ride, World 3-S in Yoshi's Woolly World.
 * Secret Swamp, World 3-S in Mario + Rabbids Kingdom Battle.