He landed the $20,000 prize on Thursday for "Tell Everyone: Why We Share and Why it Matters" (Doubleday Canada), which analyzes social media.
Hermida is associate professor at the Graduate School of Journalism at the University of British Columbia in Vancouver.
He's also worked as a BBC journalist and was a founding news editor of the BBC News website in 1997.
Hermida beat out reporter Jacques Poitras and marketing strategist Clive Veroni for the award.
This is the 30th anniversary of the prize.