The Zbarazh Castle (Ukrainian: Збаразький замок, romanized: Zbarazkyi zamok; Polish: Zamek w Zbarażu) is a fortified defense stronghold in Zbarazh, built during the times of the Polish–Lithuanian Commonwealth. It dominates the crests of the Zamkova Hills of Ternopil Oblast in Western Ukraine next to the city's central plaza that was not in so distant past surrounded by marshland. The castle existence has been credited to last members of the Polish Zbaraski family; Krzysztof and Jerzy Zbaraski.

Evidence of the City of Zbarazh formation can be seen in the Ruthenia fortress dating back to 1211 that was positioned somewhat away from current castle. Today this is a village of Zbarazky District located in the immediate proximity of Zbarazh itself and called the village of Staryi Zbarazh. At that distant time the old castle and the province was ruled by Gediminids Landlords Zbarazky.

The castle is known for being the seat of the Ukrainian aristocratic Wiśniowiecki family and its prominent members, most notably Jeremi Wiśniowiecki.

The Zbarazky landlords erected a primeval wooden fortress in the town which nowadays is called Staryi Zbarazh (Old Zbarazh), a quarter mile away from their own mansion. Soon after it was incinerated during a skirmish with the tatars. All the fortification's protectors, including Vasyl Nesvizky, the grandson of Theodore Kaributas, were killed on the burning battleground. Another castle was constructed in the same location using the same materials, and its end was enacted in the same deadly way. It was set on fire during a nomadic attack in the year of 1589 while Janusz Zbarski commanded the stronghold. Later in the beginning of the 17th century, his son decided to build a masonry structure in the new location receiving guidance from Western European architects.

The first blueprints were drafted by Vincenzo Scamozzi for Krzysztof Zbaraski, but the project did not gain approval: it would remain more a palace then a marshal bastion. Scamozzi had envision his creation at first and described it in the tractate named "The idea of universal architecture", which he later on partially embodied into stone in the city of Zbarazh. It appeared that this architect took "Utopia" of Thomas More too close to his heart. Therefore, the contender won a different project by Henryk van Peene, who was quite familiar with the landlords due to his previous work on Zbaraski's palace in Kraków.

An escarped bulwark emerged from the mounds of dirt up to 12 m (39 ft) high, and a terrace for the castle troopers was laid out of 23 m (75 ft) wide. A rectangular courtyard inside had been plotted. Behind the walls arched chambers were constructed, that nowadays house specimens of arms and wooden sculptures of Pinzel's students. An entrenchment around bulwark was very wide, in some parts it is as much as 40 m (131 ft). In the middle of the fortress, regarding rules of "palazzo in fortezza", was developed a palace in the architectural style of Renaissance with early Baroque elements.

First ruination of the new fortification was endeavored by cossacks in 1648. Polish sources reported their amount as much as 100,000 strong. But it would rather be an exaggeration. There was no business for such a ferocious army to siege a small castle. Nonetheless the landlords became determined increasing security of the military outpost. In the year of 1649 it was improved complying to a design of architect Dubois from Lorraine. During some period of time the stronghold was vacant, but later on its ownership was transferred to the Wiśniowiecki family. In 1675, it was overcome and burned by Turks, and soon afterwards followed a restoration by Dimitry Wiśniowiecki. That was exactly a moment when castle was turned into a palace, losing its strategic military designation. Nevertheless, it did not stop Russian soldiers plundering a building in the years of 1707 to 1734. Dmitry Wiśniowiecki having died in 1682, the architectural complex became a property of the Potocki family. These were Joseph and later on Stanislav, Mayor of Kyiv. Zbarazh remained under the control of the Potoki family until the middle of the 19th century.

The castle was taken by the Cossacks in 1649 and the Turks in 1675. The events of 1649 are dramatized by Henryk Sienkiewicz in his novel With Fire and Sword. Ivan Bohun was heavily wounded under the castle's walls. Ivan Mazepa and Peter I are known to have visited it in 1707.