Trout fishing has been excellent. A significant portion of fish caught have been larger than 12-inches. Diamond Lake was stocked with tiger trout. These fish are intended to assist in controlling illegally introduced tui chub. Tiger trout are catch-and-release only and need to be released immediately and unharmed if caught.

As part of the 2016 regulation simplification process, Diamond Lake is now back to the Southwest Zone regulation of 5 rainbow trout per day. Anglers that are planning on taking a trip to Diamond Lake should check with the Umpqua National Forest (541-498-2531) for information on seasonal camp and ramp closures. Anglers can check fishing and water conditions at Diamond Lake on the Diamond Lake Resort website, or call their toll free number at 1-800-733-7593, ext. 5 for updates. Diamond Lake is open year-round.