Justinić families are Croats and they are mostly from the Island of Krk. In the past century, relatively most of Croatian residents bearing this family name were born in Rijeka and on the Island of Krk. In Kras on the Island of Krk every fourth inhabitant had the family name Justinić.
About 140 people with faimily name Justinić live in Croatia today, in 60 households. There were 240 of them in the middle of the past century, and their number decreased by 40 percent. They are only located in in 6 Croatian cities and 17 other places, mostly in Kras on the Island of Krk (30), Rijeka (25), Zagreb (20), and in Omisalj (10) and Malinska (<10) on the Island of Krk.