Chasing a target of 292 on the final day, Delhi were all out for 209, losing their last six wickets for only 36 runs.
India [ Images ] discard Mishra first smashed 74 in Haryana's second innings and returned to grab four for 50, including the important wickets of Rajat Bhatia, Puneet Bisht and Mithun Manhas [ Images ].
From being comfortably placed at 173 for 4 in 44.4 overs, Delhi lost wickets in a heap and were all out in 67 overs.
Delhi, with 11 points from five matches, are placed fourth in Group B, while Haryana opened their account with six points after three straight defeats.
They are now seventh in the group.
Veteran Manhas continued his good form in the competition as he scored 73 off 149 balls, inclusive of six boundaries, and was the ninth batsman out for his side.
He did not get any support from his teammates, save Bhatia (33) with whom he added 68 runs for the fifth wicket.
The moment Bhatia was dismissed off Mishra's bowling, caught by Sachin Rana, the slide began.
Earlier, Haryana resumed at their overnight score of 167 for 6, adding another 42 runs, with Mishra adding 24 runs to his overnight not out score of 50. He hit six fours and a six in his 111-ball knock.
Sumit Narwal had best figures of five for 35, while left-arm spinner Vikas Mishra grabbed four wickets.
Haryana: 307 & 209 (Amit Mishra 74, Sumit Narwal 5-35, Vikas Mishra 4-64).
Delhi: 224 & 209 (Mithun Manhas 73, Amit Mishra 4-50).
Haryana won by 83 runs.
Haryana 6 points; Delhi 0.