R.M.S. Queen Elizabeth was an ocean-going steamship passenger liner of the Cunard Steamship Lines. She was launched on September 27, 1938 and retired in 1968. She was the largest passenger steamship ever constructed and held the record for the largest passenger ship of any kind until being surpassed in 1996. She was named for Queen Elizabeth, the wife of King George VI of the United Kingdom, who was queen consort of the United Kingdom at the time the ship was built.

The Queen Elizabeth was built in 1938 and her maiden voyage took place on March 3, 1940, after the outbreak of World War II. Her first trip was a secret trip to New York City. During the war, the Queen Elizabeth and her sister ship, the R.M.S. Queen Mary, were used as troop transports. Their high speeds allowed them to outrun hazards such as the German U-boats, allowing them to travel without a convoy.

After the war, the Queen Elizabeth, together with the Queen Mary, dominated the transatlantic passenger trade for several decades until transatlantic ocean liner travel began to decline due to the faster transatlantic travel allowed by airplanes. Both ships were retired by 1969 and replaced by a single, smaller ship: the RMS Queen Elizabeth 2 (the QE2). The QE2 was named after the Queen Elizabeth, being the second ship to bear the name.

After its retirement, the Queen Elizabeth was bought by the Hong Kong tycoon Tung Chao Yung in 1970 and made into a university. It was destroyed by fire on January 9, 1972, in Hong Kong harbour.