Igor Emmanuilovich Grabar was born on March 25, 1871, in Budapest to the public figure Emmanuil Grabar, who became a deputy in the Hungarian parliament in the late 1860s. He was baptized by an Orthodox priest of Serbian descent, with Konstantin Kuzmich as his godfather, the uncle of the artist Boris Kustodiev.

From 1880 to 1882, Igor studied at the Yegoryevsk Progymnasium and attended classes by Varvara Zhitova, the half-sister of the writer Ivan Turgenev. In 1882, he continued his education at the Tsarevich Nicholas Lyceum, graduating in 1889 with a gold medal. He then enrolled in the law faculty of St. Petersburg University, which he completed in 1893.

Unlike his older brother Vladimir, who became a well-known lawyer, Igor chose a career as an artist. In Moscow, he attended drawing classes at the Moscow Society of Lovers of the Arts. From 1892, he began studying in the workshop of Professor Pavel Chistyakov, and in 1894, he entered the St. Petersburg Academy of Arts, where he studied under Ilya Repin in 1895. In 1896, Grabar traveled to Europe and enrolled in Anton Azhbe's private studio in Munich. This period includes his works "Lady with a Dog" and "Lady at the Piano," created in 1899.

In 1901, he returned to Russia and became a member of the creative associations "World of Art" and "Union of Russian Artists," where his landscapes and still lifes were exhibited. In 1903, Grabar permanently moved to Moscow and participated in exhibitions of the "World of Art" and the "Union," as well as abroad in cities like Munich, Paris, and Rome. In the 1910s, he was part of the city jury that held facade beauty contests in Moscow.

After moving to Moscow, Grabar met the artist Nikolai Meshcherin and often visited his estate in Dugino, now the village of Meshcherino in the Moscow region.

In addition to painting, Grabar was actively involved in research and educational activities, publishing articles about art in various magazines such as "World of Art," "Scales," "Old Years," "Apollo," and "Niva."

In early 1913, the Moscow City Duma appointed him as the curator of the Tretyakov Gallery, where he worked until 1925.

Grabar played an important role in the artistic life of Soviet Russia. He was friends with Natalia Sedova, the wife of Leon Trotsky, whom he met in the museum department of the Narcompros. At the beginning of the Stalinist purges, he resigned from his posts and returned to painting, creating a popular portrait of a girl named Svetlana.

Grabar also directed the Central Restoration Workshops in Moscow in 1918 and 1930, being the initiator of their creation. From 1921, he taught a course on the theory and practice of scientific restoration at Moscow State University. From 1944, he worked as the scientific supervisor of the workshops and headed commissions for the removal of paintings and icons for their preservation. He participated in the restoration of Andrei Rublev's icon "The Trinity." The modern All-Russian Scientific Restoration Center bears his name.

Grabar was a consultant to the Scientific Council on restoration work at the Trinity-Sergius Lavra, where Ignaty Trofimov was the chief architect. From 1944, he became the director of the Institute of Art History of the USSR Academy of Sciences.

In early 1943, Grabar proposed to compensate for the losses of Soviet museums by confiscating works from museums in Germany and its allies. He headed the Bureau of Experts, which compiled lists of works from museums in Europe and prepared trophy brigades.

Igor Grabar passed away on May 16, 1960, and was buried in Moscow at Novodevichy Cemetery.