Goals from Jamie Allen, Ian Henderson and Michael Rose clinched victory for in-form Dale, with Plymouth playing the last 40 minutes with just 10 men after Andres Gurrieri was dismissed for striking defender Jack O'Connell in the face.
Rochdale were ahead as early as the fifth minute when Henderson and George Donnelly combined to set up Allen, who slid a neat finish past Luke McCormick.
Josh Lillis prevented the visitors drawing level when he kept out a fierce volley from Gurrieri while Dale midfielder Peter Vincenti had a header cleared off the line by Reuben Reid before the break.
Lillis pulled off a fine save to deny Lewis Alessandra early in the second half but once Gurrieri was sent off, the visitors were up against it.
Henderson doubled the lead with a wonder goal in the 76th minute, cutting into the area on the right and sending a left-footed half-volley into the top corner.
And Rose wrapped up the win late on when he angled a 25-yard lob over McCormick.