An important figure in the acoustic folk revival of the 1960s, his work ranged from old English ballads to Bertolt Brecht, blues, gospel, rock, New Orleans jazz, and swing. He was also known for performing instrumental ragtime guitar music, especially his transcription of St. Louis Tickle and Scott Joplin's Maple Leaf Rag.

Van Ronk was a widely admired avunc presiding over the coffeehouse folk culture and acting as a friend to many up-and-coming artists by inspiring, assisting, and promoting them. Folk performers whom he befriended include Bob Dylan, Tom Paxton, Patrick Sky, Phil Ochs, Ramblin' Jack Elliott, Guthrie Thomas, and Joni Mitchell.