I'm not for sure, but I think the only river that flows north is the St. Johns River in northeastern Florida, United States.
The only two that I'm aware of are the Red River which runs along the Minnesota/South Dakota border and into Canada, and the Nile River which starts in Central Africa and empties into the Mediterranean.
Ok If your talking about in north america there is only 3 and one is in mo. Osage river and sac river run together....down by harry S. Truman lake.
There are many rivers that flow north in North America. The St. Johns, Red, Richelieu, New, Deschutes, Bighorn and Athabasca are among some of the longest- running over 200 miles but there are many more rivers that are not as long that run north.