The Israeli–Palestinian conflict is an ongoing military and political conflict about land and self-determination within the territory of the former Mandatory Palestine. Key aspects of the conflict include the Israeli occupation of the West Bank and Gaza Strip, the status of Jerusalem, Israeli settlements, borders, security, water rights, the permit regime in the West Bank and in the Gaza Strip, Palestinian freedom of movement, and the Palestinian right of return.

The conflict has its origins in the rise of Zionism in the late 19th century in Europe, a movement which aimed to establish a Jewish state through the colonization of Palestine, synchronously with the first arrival of Jewish settlers to Ottoman Palestine in 1882. The Zionist movement garnered the support of an imperial power in the 1917 Balfour Declaration issued by Britain, which promised to support the creation of a "Jewish homeland" in Palestine. Following British occupation of the formerly Ottoman region during World War I, Mandatory Palestine was established as a British mandate. Increasing Jewish immigration led to tensions between Jews and Arabs, which grew into intercommunal conflict. In 1936, an Arab revolt erupted, demanding independence and an end to British support for Zionism, which was suppressed by the British. Eventually, tensions led to the United Nations adopting a partition plan in 1947, triggering a civil war.

During the ensuing 1948 Palestine war, more than half of the mandate's predominantly Palestinian Arab population fled or were expelled by Israeli forces. By the end of the war, Israel was established on most of the former mandate's territory, and the Gaza Strip and the West Bank were controlled by Egypt and Jordan respectively. Since the 1967 Six-Day War, Israel has been occupying the West Bank and the Gaza Strip, known collectively as the Palestinian territories. Two Palestinian uprisings against Israel and its occupation erupted in 1987 and 2000, the first and second intifadas respectively. Israel's occupation resulted in Israel constructing illegal settlements there, creating a system of institutionalized discrimination against Palestinians under its occupation called Israeli apartheid. This discrimination includes Israel's denial of Palestinian refugees from their right of return and right to their lost properties. Israel has also drawn international condemnation for violating the human rights of the Palestinians.

The international community, with the exception of the United States and Israel, has been in consensus since the 1980s regarding a settlement of the conflict on the basis of a two-state solution along the 1967 borders and a just resolution for Palestinian refugees. The United States and Israel have instead preferred bilateral negotiations, rather than a resolution of the conflict on the basis of international law. In recent years, public support for a two-state solution has decreased, with Israeli policy reflecting an interest in maintaining the occupation, rather than seeking a permanent resolution to the conflict. In 2007, Israel tightened its blockade of the Gaza Strip and made official its policy of isolating it from the West Bank. Since then, Israel has framed its relationship with Gaza in terms of the laws of war, rather than in terms of its status as an occupying power. In a July 2024 advisory opinion, the International Court of Justice (ICJ) determined that Israel continues to illegally occupy the West Bank and Gaza Strip. The ICJ also determined that Israeli policies violate the International Convention on the Elimination of All Forms of Racial Discrimination.

Since 2006, Hamas and Israel have fought several wars. Attacks by Hamas-led armed groups in October 2023 in Israel, which resulted in nearly 1,200 deaths, were followed by another war, which has caused widespread destruction, loss of life, mass population displacement, a humanitarian crisis, and an ongoing famine in the Gaza Strip. Israel's actions in Gaza during this war have been described by international law experts, genocide scholars and human rights organizations as a genocide.

The Israeli–Palestinian conflict began in the late 19th and early 20th centuries, with the development of political Zionism and the arrival of Zionist settlers to Palestine. During the early 20th century, Arab nationalism also grew within the Ottoman Empire. To gain support from the Arab nationalists in the war against the Ottoman Empire, Great Britain promised support for the formation of an independent Arab state in Palestine in the McMahon–Hussein correspondence. The British Empire supplied a large amount of weapons to the Arab revolt 1916-1918. With support from the Arab revolt the British Empire defeated the Ottoman's forces and took control of Palestine, Jordan and Syria. It later transpired that the British and French governments had secretly made the Sykes-Picot Agreement in 1916 not to allow the formation of an independent Arab state. In July 1920, the short-lived Arab Kingdom of Syria, with Emir Faisal (one of the leaders of the Arab Revolt) as king and tolerated by Britain, was crushed by French armed forces, equipped with modern artillery.

While Jewish colonization began during this period, it was not until the arrival of more ideologically Zionist immigrants in the decade preceding the First World War that the landscape of Ottoman Palestine would start to significantly change. Land purchases, the eviction of tenant Arab peasants and armed confrontation with Jewish para-military units would all contribute to the Palestinian population's growing fear of territorial displacement and dispossession. From early on, the leadership of the Zionist movement had the idea of "transferring" (a euphemism for ethnic cleansing) the Arab Palestinian population out of the land for the purpose of establishing a Jewish demographic majority. According to the Israeli historian Benny Morris the idea of transfer was "inevitable and inbuilt into Zionism". The Arab population felt the threat of transfer as early as the 1880s with the arrival of the first aliyah. Chaim Weizmann's efforts to build British support for the Zionist movement would eventually secure the Balfour Declaration, a public statement issued by the British government in 1917 during the First World War announcing support for the establishment of a "national home for the Jewish people" in Palestine.

With the creation of the British Mandate in Palestine after the end of the first world war, large-scale Jewish immigration began accompanied by the development of a separate Jewish-controlled sector of the economy supported by foreign capital. The more ardent Zionist ideologues of the Second Aliyah would become the leaders of the Yishuv starting in the 1920s and believed in the separation of Jewish and Arab societies.