The cross has been recognized as a great architecture solution idea in classical Greek, Hellenistic sacral tradition of the Syrian and Palestinian Cultural Heritage and the Roman-era cemetery architecture from the Early Christian architecture. The cross-shaped churches were built on the previously mentioned basilica model, in the form of a cross, from the end of the 4th century, but mostly in the 5th to 6th century. The earliest example of this style is the Church of the Holy Apostles, but the remains of the church no longer exist. Most churches in the Roman Province of Dalmatia, both in urban and rural areas, were built in the shape of a cross in the 5th to 6th century. One of the cruciform churches – in Martinšćica was finished in the 4th century, which was estimated using the Carbon-14 dating method. This paper will discuss thirteen Early Christian sites - in the form of a cross, located in the Republic of Croatia and in Bosnia and Herzegovina: Baška, Fulfinum, Cickini, Martinšćica, Salona (three examples), Lovrečina, Polače, Erešove bare, Majdan – Mrkonjić Grad, Oborci and Blagaj. These sites have different profiles, but all of them are classified as the cross-shaped plans (the Latin cross, the Greek cross and the Tau cross form). While some of the churches have the actual transept form, baptisterium and the graves located all around the church area, some of them don't have all of these church architectural elements. The graves inside an altar were not found in all of the mentioned churches, but placing relics of saints inside an altar was an extremely important practice for Christians, so the tombs were probably there, despite the fact that they were not found.