Abstract: A straw adaptor for a baby bottle comprised of an elongate tube having a first end adapted for drinking from and a second end adapted to be submerged in a drinking liquid in a baby bottle is disclosed. The first end is curved and flattened and the second end is straight and extends nearly to the bottom of a baby bottle. The device further includes a flattened, disc-shaped collar nearer its first end, this collar being integral with the tube and oriented in perpendicular relation to its long axis. The collar has a concentric, upstanding ridge on its upper face which registers with the inside edge of a threaded, annular baby bottle cap. Alternative embodiments further include a unidirectional valve and a mouthpiece with convolutions for added flexibility.