A cousin of the Crimean War general Mikhail Dmitriyevich Gorchakov. Aleksandr Gorchakov grew up in the European atmosphere of salon and court life in St. Petersburg. Entering the diplomatic service in 1817, he became a member of the Russian delegations to the international congresses of Troppau, Laibach, and Verona (1820–22), and, despite the efforts of the foreign minister Count Karl Robert Nesselrode to retard his advancement, he was appointed (after 1822) to posts in various Russian embassies throughout western Europe, including Vienna, where he gained particular prominence as ambassador to Austria during the Crimean War.

When Nesselrode resigned as foreign minister after the Crimean War, Gorchakov was chosen as his successor (April 1856). He immediately embarked on a policy of reaffirming Russia as a great European power and strove to establish cordial relations with France and Prussia. Although he could not maintain the Franco-Russian rapprochement when Russia, over French protests, suppressed the Polish insurrection of 1863, he effectively conducted diplomacy with the other European powers and obtained Prussia's open support for Russia's actions. In 1866 Tsar Alexander II rewarded him by naming him to the post of imperial chancellor.

Pursuing his aim of increasing Russia's stature, Gorchakov took advantage of Europe's preoccupation with the Franco-German War in 1870 to renounce the prohibitions, placed on Russia after the Crimean War, against maintaining a war fleet in the Black Sea and fortifying the coastline. He also brought Russia into a loose defensive alliance with Germany and Austria-Hungary ( Dreikaiserbund, or Three Emperors' League; 1873).

Despite his achievements, Gorchakov's role in determining Russia's foreign policy began to diminish in the mid-1870s—his personal rivalry with the German chancellor Otto von Bismarck interfered with the effectiveness of the Dreikaiserbund; his disapproval of Pan-Slavism was insufficient to prevent it from becoming a major influence on Russian foreign policy; and his attempts to preserve the Dreikaiserbund and the peace following a Bosnian revolt in 1875 failed. Furthermore, after the Russo-Turkish War of 1877–78, he could neither prevent his subordinate Count Nikolay Ignatyev from imposing the harsh Treaty of San Stefano (San Stefano, Treaty of) on the defeated Turks nor stop the European powers from intervening and replacing the San Stefano settlement with the far less favourable (to Russia) Treaty of Berlin. Although he considered the Berlin treaty the greatest failure of his official career, Gorchakov did not retire from his posts of foreign minister and chancellor until 1882.