A one-pot reaction to synthesize functionalized 2H-azirines through visible-light-mediated ring contraction and olefinmetathesis of isoxazoles is described. Hoveyda–Grubbs II catalyst was found to function as a photocatalyst for these transformations, allowing these processes to be carried out in a one-pot manner. This study offers a new entry for the application of Grubbs catalysts as efficient photocatalysts