Sheikh Maktoum, who was also the ruler of the emirate of Dubai, died in Australia on Wednesday. It is thought he had previously suffered from heart problems.
A statment on behalf of Sheikh Khalifa bin Zayed al Nayhan, the president of the UAE, said, "The UAE today lost a historical leader who has contributed throughout his life in establishing the UAE and enhancing its structure and the welfare of its people."
Sheikh Maktoum maintained a low profile during his reign. He left the day-to-day affairs of running Dubai to his younger brothers, particularly Sheikh Mohammed bin Rashid Al Maktoum, the crown prince.
Anthony Harris, a former British ambassador to the UAE, said, "In his quiet way, Sheikh Maktoum was a pillar of the federation. He was very simple and very wise and was remarkable for an Arab leader because he allowed his younger brothers to have a higher profile."
Sheikh Mohammed, a globally renowned entrepreneur, is expected to be confirmed as his brother's successor as the ruler of the emirate, the Gulf's booming trade and tourism hub.
Internationally, Sheikh Maktoum was perhaps best known as co-owner of Godolphin, the Dubai stables that own some of the world's finest racehorses and compete in all the major races.
He succeeded his father as the emir of Dubai and the prime minister of the UAE after his death in 1990. He also served in the latter role between 1971 and 1979.
He was born in 1943.
Sheikh Maktoum's body will arrive back in Dubai on Thursday morning. Prayers and the funeral will take place in the Za'abel mosque.
Forty days of mourning have been declared, and government offices will close for seven days from Wednesday.