In 1484–1494 in Grobnik he copied the Drugi novljanski brevijar ("The Second Novi Vinodolski Breviary") for the Pauline monastery in Novi Vinodolski, a Glagolitic codex in 500 folios.
Katičić has charted the meanderings in the continuity of Croatian language and literature, from the earliest stone inscriptions and Glagolitic medieval literature in the Croatian recension of Church Slavonic to the works of Renaissance writers such as Marin Držić and Marko Marulić, who wrote in a Croatian vernacular.
In 1971 he served as an assistant to the professor Eduard Hercigonja at the Department for Old Church Slavonic (today called Department for Old Church Slavonic language and Croatian Glagolitic), since 1982 serving as a docent and since 1986 as a regular professor.