This dataset shows the distribution of neutral hydrogen in and around the M81 galaxy triplet (M81, M82, NGC 3077) and consists of a 3° × 3°, 105-pointing, high-resolution neutral hydrogen (H I) mosaic obtained with the Very Large Array C and D arrays. The data are described in the paper by de Blok et al. (2018). Here we provide the following data products: Cubes: the natural-weighted cube of the VLA C+D mosaic: m81.nat.cube.fits the robust-weighted cube of the VLA C+D mosaic: m81.rob.cube.fits the natural-weighted cube using only D-array-like baselines: m81_D.nat.cube.fits the natural-weighted and zero-spacing corrected data cube of the VLA C+D array and GBT single-dish data from Chynoweth et al. (2011): m81.zero.cube.fits Moment maps: natural-weighted zeroth (column density), first (velocity field) and second (velocity dispersion) moment maps of the VLA C+D mosaic: m81.nat.mom[0,1,2].fits robust-weighted zeroth (column density), first (velocity field) and second (velocity dispersion) moment maps of the VLA C+D mosaic: m81.rob.mom[0,1,2].fits natural-weighted zeroth, first and second moment maps of the "D-array" mosaic: m81_D.nat.mom[0,1,2].fits zero-spacing corrected natural-weighted integrated HI map (zeroth-moment) of VLA C+D and GBT data: m81.zero.mom0.fits Acknowledgements: If you make use of these data please cite the original paper: de Blok et al. (2018) - de Blok, W.J.G., Walter, F., Ferguson, A.M.N., et al. 2018, ApJ, 865, 26 (10.3847/1538-4357/aad557)