Inland Fisheries Ireland has reopened the Moy Fishery in Co Mayo, and the Galway Fishery in Galway city.
Both fisheries were closed to angling nearly two weeks ago due to elevated water temperatures.
Head of Operations at Inland Fisheries Ireland Barry Fox said: "We are lifting our cessation of angling protocols at the Moy and Galway fisheries.
"Water temperatures have reduced to appropriate levels, and when taking weather forecasts into account it is now considered appropriate to reopen both fisheries.
"Water temperatures and weather forecasts will continue to be monitored on both fisheries over the coming weeks."
Salmon and trout angling had been suspended at the two fisheries in the west, as a result of high water temperatures and the impact that they may have on stocks.
It followed temperature recordings in excess of 20C in recent weeks.
This level of heat can cause "thermal stress", which can lead to fish kills.
The Galway Fishery and the Moy Fishery are both now up and running. Management at both fisheries will be contacting all anglers who have confirmed bookings over the coming days.
Those anglers who have had fishing cancelled due to the elevated temperatures will be refunded in due course.
