Beautiful Dreamer is a parlor song by American songwriter Stephen Foster (July 4, 1826 – January 13, 1864). It was published posthumously in March 1864, by Wm. A. Pond & Co. of New York. The first edition states on its title page that it is "the last song ever written by Stephen C. Foster, composed but a few days prior to his death." However, Carol Kimball, the author of Song, points out that the first edition's copyright is dated 1862, which suggests, she writes, that the song was composed and readied for publication two years before Foster's death. There are at least 20 songs, she observes, that claim to be Foster's last, and it is unknown which is indeed his last. The song is set in 9/8 time with a broken chord accompaniment.
The song tells of a lover serenading a "Beautiful Dreamer" who is oblivious to worldly cares and may actually be dead. Foster's works feature many dead young women, including his sister Charlotte and "Jeanie". Helen Lightner writes, "This sentimental ballad is folk-like in character with its repetitious but lovely melody and its basic harmonic accompaniment... The quiet and calm of this mood is portrayed by the monotony of the arpeggiated accompaniment, by the repetitiveness of the melodic pattern, and by the strophic form itself."