Yes, there is good fishing in the Panama Canal Zone, an area adjoining Panama City, Panama. I recommend fishing in Lake Gatun. If you are going to fish, you should definitely get an early start to your day, so you can maximize your catch. The most common and popular fish in the Panama Canal Zone are Peacock Bass and Oscars. If you are skilled (and lucky) you might find Snook & Tarpon as well.
If you'd like to get a "first hand feel" for what it's like to fish Lake Gatun in the Panama Canal Zone around Gamboa, please watch the video I embedded above. You'll also see some beautiful scenery.