Although he was influenced by Impressionism and Cubism, Dalí is most famous for his Surrealist paintings.

His best-known work, The Persistence of Memory introduced the image of the soft melting pocket watch. It has been described as "a Surrealist meditation on the collapse of our notions of a fixed cosmic order."

The orange clock at the bottom left of the painting is covered in ants. Dalí often used insects in his paintings as a symbol of decay. There is also a fly sitting on one of the melting watches, which some critics have interpreted as casting a human shadow.

Nine months before Salvador Dalí was born, his older brother (who was also named Salvador) died of gastroenteritis. When he was five, Dalí's parents took him to visit the grave and told him he was a reincarnation of his brother. The artist came to believe this was true and once said that his brother "was probably a first version of myself but conceived too much in the absolute." Images of his deceased sibling appear scattered throughout his later works, including Portrait of My Dead Brother.

On February 6, 1921, Dalí's mother died of uterine cancer. He later said his mother's death "was the greatest blow I had experienced in my life. I worshipped her.... I could not resign myself to the loss of a being on whom I counted to make invisible the unavoidable blemishes of my soul."

In 1927, Dalí designed the scenery for Federico García Lorca's romantic play Mariana Pineda. Although, he publicly claimed to have rejected Lorca's sexual advances, Dalí's friendship with Lorca was to remain one of his most emotionally intense relationships until the poet's death at the hands of Nationalist forces at the beginning of the Spanish Civil War, and Dalí would continue to include frequent references to Lorca in his art and writings for the remainder of his life.

In the 1960s, Dalí got a pet ocelot named Babou, which accompanied him on a leash and studded collar nearly everywhere he went--including, famously, a restaurant in Manhattan. When a fellow diner became alarmed, he calmly told her that Babou was a normal cat that he had "painted over in an op art design."

In the mid-1920s Dalí grew a neatly trimmed moustache. In later decades he cultivated a more flamboyant one in the manner of 17th-century Spanish master painter Diego Velázquez. This version became a well known Dalí icon.

Influenced by his reading of Freud, Dalí introduced suggestive sexual imagery and symbolism into his work. He submitted Dialogue on the Beach (Unsatisfied Desires) to the Barcelona Autumn Salon for 1928, but the work was rejected because "it was not fit to be exhibited in any gallery habitually visited by the numerous public little prepared for certain surprises."

In August 1929, he met his lifelong muse and future wife Gala, born Elena Ivanovna Diakonova. She was a Russian immigrant ten years his senior, who at that time was married to Surrealist poet Paul Éluard. The two immediately began a passionate love affair, and less than four months later, Gala left her husband and moved in with Dalí. Their relationship would last over 50 years, during which time Gala, who herself engaged in extra-marital affairs, seemed to tolerate Dalí's dalliances with younger muses, secure in her own position as his primary lover.