The available data of the microwave spectrum of vinyl cyanide are critically reviewed and tabulated. Molecular data such as rotational constants, centrifugal distortion constants, hyperfine coupling constants, dipole moments, and structural parameters are tabulated. Rotational transitions from 400 MHz to 200 GHz, which are likely to be of interest to radio astronomy, are calculated and tabulated along with their estimated 95% confidence limits. © 1981, American Association of Physicists in Medicine. All rights reserved.