Early in his youth La Tour went to Paris, where he entered the studio of the Flemish painter Jacques Spoede. He then went to Reims, Cambrai (1724), and England (c. 1725), returning to Paris to resume his studies in about 1727.

In 1737 La Tour exhibited the first of a splendid series of 150 portraits that formed one of the glories of the Salon for the next 37 years. He was able to endow his sitters with a distinctive air of charm and intelligence, and he excelled at capturing the delicate play of facial features. Among his subjects were the writers Jean-Jacques Rousseau (Rousseau, Jean-Jacques) and Voltaire, the painter Joseph Vernet (Vernet, Joseph), and the philosopher Jean Le Rond d'Alembert (Alembert, Jean Le Rond d'), as well as Louis XV and his mistress, Mme de Pompadour (Pompadour, Jeanne-Antoinette Poisson, marquise de), of whom he did a life-size portrait (1756). In 1746 he was received into the Academy and in 1751 was promoted to councillor. La Tour was made portraitist to the king in 1750, a position he held until 1773. La Tour retired at age 80 to Saint-Quentin.