The results of an experimental investigation to improve the performance of a discharge‐pumped iodine monofluoride laser are reported. Lasing was observed at 478.7, 484.7, 490.7, and 496.5 nm. Electrical measurements of the discharge characteristics permitted the energy flow in the circuit to be followed and laser efficiencies to be calculated. Parametric studies of gas mixtures were carried out. By optimizing several parameters, single‐pulse lasing energies greater than 50 mJ were obtained.