Mario Pantanali, from Vicenza, was taking part in the Trail Dei Tre Castelli event when he was hit by a lightning bolt while running along a 1,100 metre-high track, close to Mount Cuarnan in Italy's Friuli-Venezia Giulia region.
Concerns were raised after he failed to make it to the finishing line. A mountain search team was dispatched and his body was found a few hours later with severe burns to his chest and a leg.
Pantanali had been running along a 32km route that took him through a densely wooded path.
The organizers of the race wrote on Facebook on Monday morning: “At this time our only thoughts and words are for Mario and his family.”
The accident came as violent storms swept through much of Italy over the weekend, brought on by cyclone Poppea.
Red and higher orange weather alert warnings were issued for most of Italy's northern regions, while warnings were also issued in Lazio, Molise and Sicily.
The low air pressure brought by the cyclone saw temperatures plummet by up to ten degrees Celsius nationwide.
Strong winds and heavy rain are forecast to hit the north again on Thursday, before sunshine and warmer temperatures return in time for the weekend, according to 3bmeteo.com.