The 1973 Galway Senior Hurling Championship was the 76th completed staging of the Galway Senior Hurling Championship since its establishment by the Galway County Board in 1887.
Castlegar entered the championship as the defending champions.
The final, a replay, was played on 26 August 1973 at Duggan Park in Ballinasloe, between Castlegar and Ballinasloe, in what was their second meeting in the final overall. Castlegar won the match by 4âÂÂ11 to 3âÂÂ10 to claim their 15th championship title overall and a second consecutive title.