He traveled to Warsaw in 1905. In his travels through the Russian empire he was drafted into the Russian army, but then released as he was an only son.

David Remez was accepted as a law student in Kushta in 1911. There he met David Ben-Gurion and Yitzhak Ben Zvi. In 1912, he joined the Ottoman Turkish army along with them. The three soon left the army and Remez returned to Russia in preparation for Aliya (immigration). In Russia, he married Liba Remez and they came on Aliya in 1913, part of the Second Aliya. 

David Remez settled near Kastina (Beer Tuvia) and worked as an agricultural laborer in Ben Shemen, Be'er Tuvia and Karkur. At the outbreak of World War I David Remez and his wife moved to Zikhron Ya'akov and was active in politics and war work there. He worked with Dr. Hillel Yaffe to take care of war casualties.

After the Ottoman army invaded Zikhron Ya'akov, David and Liba moved to Tel Aviv and settled there at the request of labor leaders. He became an editor of the magazine Kuntras along with Berl Katznelson.

In 1919, David Remez was among the founders of the Achdut Ha'avoda party and in 1920 he participated in the foundation of the Histadrut labor federation. He served on the executive committee of the Histadrut and in the Vaad Leumi.

David Remez served as Director of the Public Works Office of the Histadrut from 1921 to 1929 (later "Solel Boneh"). Remez was a member of the Tel Aviv city council from 1921 to 1925, and was a founding member of the Mapai party. He became First Secretary of the Histadrut in 1935, a position he retained until 1945. Under his leadership the Histadrut expanded its leadership. In 1936 he helped to create the Port of Tel Aviv as an alternative to the port of Yaffo, which had been closed by Arab strikers during the Arab Revolt. He also created "Nachson," which evolved into the Zim maritime lines.  

Remez was also  chairman of  the Va'ad HaLeumi from 1944-1949, during the difficult period of struggle against the British and the Israel War of Independence. In June of 1946 he was arrested on the "Black Sabbath" and interned by the British in Latrun for four months.

David Remez  was among the signatories of the Israel declaration of independence and member of the provisional government. Remez was appointed Minister of Transportation on 14 May 1948. He remained at this post after the formation of the first government following the first Knesset elections in 1949.

David Remez was known as a linguist and intellectual and coined many new Hebrew words. In addition to be Minister of Transportation, he was a member of the Education Committee.  When the first government collapsed in November 1950, Remez became Education Minister in place of Zalman Shazar. Remez and the Israeli government were faced with the impossible task of providing teachers for hundreds of thousands of new immigrant students who had arrived in 1949 and 1950. Many of them spoke no Hebrew and some came from illiterate families. He appealed to the Jewish communities in the United States to send teachers to Israel. He promised to pay transportation and return them after two years, but his appeal went unanswered. In a speech, he asked where Israel could recruit teachers, since the entire Jewish population of Europe had been wiped out. 

David Remez died in office on May 19, 1951 after a brief illness. Numerous areas, streets, squares and institutions bear his name, including the Haifa neighborhood Ramot Remez, Remez Square in Jerusalem and streets in nearly every town. His son, Aharon Remez was a founder of the Haganah air service, the second commander of the Israeli Air Force and a member of the Knesset..