In Croatia, Ploj families are predominantly Croats (from Pula ), very rarely Serbs, and . In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and in Mursko Sredisce area.
Prevalence
About 10 people with faimily name Ploj live in Croatia today, in 7 households. There were 10 of them in the middle of the past century, and their number remains constant. They are located in two Croatian cities only, in Zagreb (10) and Pula (<5).