Zadar County (Croatian: Zadarska županija) is a county in Croatia, it encompasses northern Dalmatia and southeastern Lika. Its center is the city of Zadar.

According to the 2001 census, Zadar County has population of 162,045. Croats make up the majority with 93.30% of the population, while Serbs, Bosniaks, Albanians and Italians form the remainder.

Among the largest towns in the county of Zadar are: Zadar, Benkovac, Bibinje, Biograd, Nin, Obrovac and Pag.

The county of Zadar includes the islands of Dugi otok, Ugljan, Pašman and most of Pag, as well as a number of other, smaller islands. It also features the Paklenica national park.

The county's area is 7,854 km², 3,642 km² is land, which accounts for 6.4 % of the territory of Croatia. The sea area of the County is 3,632 km² (around 12% of the territorial waters) and the insular area is 580 km², with more than 300 smaller and larger islands (Zadar archipelago). The length of its coastline (including the islands) is 1,300 km.

The county's population is 200,936 (accounting for 4.5 % of the total Croatia's population), of which 129,000 people live in the coastal area, 21,000 on islands and 50,000 in the County's inland.

Zadar (see historical names) is a city in Croatia on the Adriatic Sea. It is the centre of Zadar county and the wider northern Dalmatian region. Zadar is a historical center of Dalmatia as well as the seat of the Roman Catholic Archdiocese of Zadar.

In antiquity, Iadera and Iader, the much older roots of the settlement's names were hidden, the names being most probably related to a hydrographical term. It was coined by an ancient Mediterranean people and their Pre-Indo-European language. They transmitted it to later settlers, the Liburnians. The name of the Liburnian settlement was first mentioned by a Greek inscription from Pharos (Stari grad) on the island of Hvar in 384 BC, where the citizens of Zadar were noted as Ίαδασινοί (Iadasinoi). According to the Greek source Periplus of Pseudo-Scylax the city was Ίδασσα (Idassa), probably a vulgar Greek form of the original Liburnian name.

During Antiquity the name was often recorded in sources in Latin in two forms: Iader in the inscriptions and in the writings of classic writers, Iadera predominantly among the late Antiquity writers, while usual ethnonyms were Iadestines and Iadertines. The accent was on the first syllable in both Iader and Iadera forms, which influenced the early-Medieval Dalmatian language forms Jadra, Jadera and Jadertina, where the accent kept its original place.