Superoxide reductase is an enzyme that catalyzes the conversion of highly reactive and toxic superoxide (O₂⁻) into less toxic hydrogen peroxide (H₂O₂):

reduced rubredoxin + O₂⁻ + 2 H⁺ ${\displaystyle \rightleftharpoons }$ rubredoxin + H₂O₂

Fe²⁺ + O₂⁻ + 2 H⁺ ${\displaystyle \rightleftharpoons }$ Fe³⁺+ H₂O₂

Hydrogen peroxide in turn is reduced to water by rubrerythrin. The 3 substrates of this enzyme are reduced rubredoxin, superoxide, and H⁺, whereas its two products are rubredoxin and H₂O₂.

This enzyme belongs to the family of oxidoreductases, specifically those acting on superoxide as acceptor (only sub-subclass identified to date). The systematic name of this enzyme class is rubredoxin:superoxide oxidoreductase. Other names in common use include neelaredoxin, and desulfoferrodoxin.