In a semiconductor laser device, an AlGaN buffer layer, a GaN layer, an n-GaN layer, an n-AlGaN cladding layer, an MQW light emitting layer, a p-AlGaN cladding layer, a p-first GaN cap layer, a current blocking layer composed of n-AlGaN, and a p-second GaN cap layer are stacked in this order on a sapphire substrate, and a ridge portion having an upper surface having a width W.sub.1 is formed by etching. The current blocking layer has an opening having a width W.sub.2 on the upper surface of the ridge portion. The width W.sub.2 of the opening is smaller than the width W.sub.1 of the upper surface of the ridge portion. Accordingly, in a light emitting region of the MQW light emitting layer, a saturable light absorbing region is formed on both sides of a current injection region.