Morioka Hiroyuki (森岡浩之: 1962-) is a Japanese sci-fi novelist. In 1992 his first novel Yume no ki ga tsugeta nara ("If we can plant a dream-tree") appeared in Hayakawa Shoten (Tokyo)'s SF Magazine. His characteristics include a deep interest for linguistics (specially for conlangs), artificial intelligence, bitter humor, and well-designed world settings.

In 1996 he published his first long novel in three volumes, Seikai no Monsho (Crest of the Stars). In the next year 1997 Seikai no Monsho was awarded with Seiun-sho from Japan SF Convenion . He released its sequel Seikai no Senki (Banner of the Stars ), where he said that Seikai no Monsho was actually an overture to Seikai no Senki. Morioka had already suggested in Seikai no Monshou 2 that the entire series should narrate the life of Princess Lamhirh (aka Lafiel), from her birth to her eventual ascention to the imperial throne. Three volumes of Seikai no Senki are now available and Morioka named them "Diahoc Trilogy" but the series itself has not yet finished.

Aside from the Seikai series, he published another Senki in 4 volumes, based on Japanese mythology.