Jenny Lake is a great place to fly fish for the angler who wants great scenery and also good access. There is a boat dock at the south end of the lake for anyone who wants to put in a boat (be sure to get a boat permit in Teton Park). The lake is also encircled by a hiking trail, which gives great access for those foot bound anglers. Both cutthroat and lake trout can be found, but the concentration of cutthroat is higher than in Jackson Lake.
Most people fly fish Jenny after ice out, which is usually about mid May, but can be earlier during warmer winters. The fishing at ice out is generally good with streamers and wooly buggers, but gets better as the water warms and some insect hatches begin to appear. When the flying black ants are out in June, the surface fishing can be very good.
Fishing is generally good with streamers throughout the summer. Popular fly fishing patterns include Black Wooly Bugger, Kiwi, Zonker and Mohair Leeches.
A lot of the best fishing is along the mountain side of the lake. See the yellow on the below map.