Billionaire Macau shipowner and gambling tycoon Stanley Ho has died aged 98.

Best known for transforming Macau into the world's gaming capital, Ho had maritime interests including ferries, cruiseships and bulkers.

According to The Wall Street Journal, citing family, he died in his sleep at Hong Kong Sanatorium Hospital.

Ho was known as "the King of Gambling". His efforts saw Macau transformed from a small Portuguese colony into a gambling hub, home to 41 casinos, roughly half of which are owned by his company SJM Holdings. His 40-year monopoly on gaming in the city lasted until 2002, earning him billions.

His involvement in shipping stretched back to 1961, when he began running ferries between Macau and Hong Kong. Those ferries continued to run under the auspices of Shun Tak Holdings.

In the late 1990s, Ho made moves into the emerging gambling cruise market. In the early 2000s, he considered making a play into tankers and reportedly had bulker interests through Portuguese outfit Portline and alongside Chinese owner Li Zhaoxia.

In 2017, he stepped down from Shun Tak Holdings, putting his daughter Pansy Ho in charge. He retired from SJM the next year.

A flamboyant figure, Ho reportedly married four times and fathered 17 children. He was said to have shunned gambling and owned race horses and was a well-known philanthropist, helping to fund Macau's airport.

"Our four families ... stand united in our grief and respect for his legendary accomplishments and everything he has done in life for Hong Kong and Macau, and all his charitable donations," Angelo Ho, his eldest surviving daughter, told The Wall Street Journal.