Opting to bat, Karnataka rode on R Samarth's 111 to notch up 290 for nine in the stipulated 50 overs.
In reply, Mumbai were restricted to identical score as Karanataka finished ahead of Bengal and Bangladesh to set up a final clash against the same side.
Both teams will clash in the final tomorrow.
Brief Scores:
Karnataka: 290/9 in 50 overs (R Samarth 111, Kunal Kapoor 69; Saurabh Netravalkar 5/50) tie aginst Mumbai 290/9 in 50 overs (Akhil Herwadkar 71, Shreyas Iyer 69, Sarfaraz Khan 45; Udit Patel 3/43).