"The crown prince will return home at 8.00pm (1700 GMT) Wednesday from Britain," said a statement carried by the state owned KUNA news agency.
No details were given on the condition of the 75-year-old prince, who has repeatedly been admitted to hospital in Kuwait, Britain and the United States since undergoing colon surgery in 1997.
Saad's return coincides with a flare-up of a crisis within the al-Sabah ruling family that prompted the amir, Shaikh Jaber al Ahmad al-Sabah, to step in publicly on 10 October to defuse the tension.
Shaikh Jaber expressed "complete trust" in his powerful prime minister and half-brother Shaikh Sabah al-Ahmad al-Sabah, whose government had been recently criticised by a leading ruling family member.
Shaikh Salem al-Ali al-Sabah, head of the National Guard, proposed a three-member committee to assist the ailing leadership, in the strongest call to date for change within the ruling family.
The amir has also promised a "swift resolution" of the crisis.
Saad, a cousin of the amir, became crown prince in 1978.
He was also prime minister from February 1978 until July 2003, when he was replaced by Shaikh Sabah after his health worsened.
The health problems of members of Kuwait's ruling family have fuelled speculation of a shake-up in the emirate, with many speaking of the possibility of appointing Shaikh Sabah as crown prince.
The amir says he trusts the PM
Shaikh Sabah al-Ahmad al-Sabah
The amir, who suffered a brain haemorrhage in September 2001, returned home in August, two and a half months after undergoing leg surgery in the United States.
The 77-year-old amir has delegated most of his public duties to the prime minister.
Al-Taleea weekly, a Kuwaiti paper, called on Wednesday for resolving the dispute according to the constitution in a way that would "preserve Kuwait's stability and harmony within the ruling family."
The solution "should not however change persons only, but it should change the course of reforms ... and eliminate corruption," the weekly said.
The al-Sabah family has ruled Kuwait for 250 years.