There are people who go to the Presa Allende Reservoir on the outskirts of San Miguel de Allende to fish. I wouldn't characterize fishing in the reservoir as particularly good or something that people would seek out to do, but I have friends who have a reel, drink beers and throw a line out. Presa Allende Reservoir is not a fisherman's destination per se but I wouldn't be surprised if there were some good fishing areas that are a little off the radar because there are so many haciendas that probably stock fish.
The nearest ocean from San Miguel de Allende is a day’s drive.
(Beer on the coast of Mexico, pictured.)