Harvest Time Blues (also referred to as the Monaghan Rhythm and Blues Festival) is an annual music festival held in Monaghan town, in Ireland. Since its launch in 1990, it has become one of the one of Ireland's leading live music festivals. Several noted performers have appeared at the festival, including Van Morrison, Peter Green of Fleetwood Mac, and ex-Rolling Stones guitarist Mick Taylor.

The festival takes place in Monaghan town, with venues located across the town, though the main stage is typically located in a large marquee in the New Road/Glen Road car park. Pubs across the town play host to smaller gigs in what is collectively known as the Blues Trail.