Fisheries management of Parapristipoma trilineatum around Mugi-oshima Island on the Pacific coast of Tokushima Prefecture was examined based on spawning per recruit analysis. %SPR of the present stock is 18.6%. The minimum size limit of the present fisheries regulation is 20 cm FL, and fish under the minimum size must be released. The ideal status (%SPR=30 or 35%) can be attained by reducing the fishing coefficient on two year old fish by 54.4% or 73.0%, respectively, and prohibiting fishing on fish younger than one year old. The target %SPR can be gained by raising the minimum size from 20 cm to 23 cm or 24 cm.