Slovenia is bordered by four countries.
Austria ( listen ) , is a federal republic and a landlocked country of over 8.7 million people in Central Europe . Croatia ( [ kroʊˈeɪʃə ] ; Hrvatska [ xř̩ʋaːtskaː ] ) , officially the Republic of Croatia ( [ Republika Hrvatska , links = no ] , ) , is a sovereign state between Central Europe , Southeast Europe , and the Mediterranean . The Kingdom of Hungary ( Hungarian : Magyar Királyság ) , also known as the Regency , existed from 1920 to 1946 as a de facto country under Regent Miklós Horthy . The Kingdom of Italy ( Regno d'Italia ) was a state founded from 1861 , when King Victor Emmanuel II of Sardinia was proclaimed King of Italy , to 1946 , when a constitutional referendum led civil discontent to abandon the monarchy and form the Italian Republic . Slovenia . It is bordered by Italy to the west , Austria to the north , Hungary to the northeast , Croatia to the south and southeast , and the Adriatic Sea to the southwest .