As sunset falls on his private island in the South China Sea, entrepreneur Lin Dong likes few things better than to lounge on a hammock strung between two trees as waves lap the shore.

"I don't like noise, and I'm not a fan of the pollution in crowded cities," he said. "The island life suits me much better".

Lin made his fortune after founding a medical equipment company and is one of a small but growing number of wealthy Chinese acquiring their own islands.

Thin with a greying goatee, the 42-year-old says uncertainty over bureaucratic land ownership restrictions blights his fruit tree-strewn paradise.

"I don't dare to invest in the island, anything I build on it could be demolished," he told AFP.

There are at least 600 island owners in China, he estimates, mostly corporations planning tourism or fishing development, but also individuals who build private clubhouses to entertain friends and officials.

But Lin counts himself amongst an elite group who buy them for pleasure alone -- and has founded China's first association of island owners.

Its members "love nature, beaches, and lying on our backs listening to music", added Lin, who favours melodic singer-songwriters.

Lawyer Wang Yue, 41, commutes from China's commercial hub Shanghai to a one square kilometre uninhabited island about 40 kilometres from the coast.

"On the island at night you can see a sky full of stars, and the moon rising from the east. That's a great feeling," he said.

A few weeks ago Lin arranged the second "Chinese Island Owners Forum", on the sidelines of a luxury goods trade fair touting sports cars, yachts and private helicopters in his home province of Guangdong.

Beside a small artificial beach, models in bikinis and feathery wings lined up behind the panellists and a host declared: "A dream of a private kingdom is in all our hearts.

"That dream is of a beautiful island."

- Playing around -

China claims 14,500 kilometres of coastline and 7,300 islands of more than 500 square metres -- all owned by the government and many in the disputed South China Sea where it is also building atop reefs to back up its territorial ambitions.

Aspiring Robinson Crusoes were in legal limbo until 2010 when a new law allowed the sale of island land use rights, valid for 50 years.

The eastern province of Zhejiang held its first "island auction" a year later, with one company paying 20 million yuan for the contract to an uninhabited isle of more than 2.5 hectares.

Several other provinces have followed suit, but Lin said that such permits tend to be awarded to companies rather than individuals.

"We hope the government will come out with policies to support us, or at the very least won't oppress us," he said.

Lin's association has 53 members, overwhelmingly male, and its wooden clubhouse naturally stands on an island, named Guanlong, in a river running through Guangzhou, the capital of Guangdong in southern China.

Lin paid for his unnamed island off neighbouring Guangxi region in 2009 -- before China's island law took effect, leaving him potentially at risk of eviction.

A businessman who leased an island in Guangdong in the 1990s has become embroiled in a protracted legal battle after the local county government declared his ownership rights "invalid" in 2012.

Worried about the security of his sea purchase, Lin splashed out for another -- in a lake, where he says he feels more free.

- A private treat -

With more than a million dollar millionaires, China has plenty of people who can afford a chunk of sea land, but the restrictions at home are driving some to foreign shores.

Recent reports said a Chinese woman, Wendy Weimei Wu, had bought New Zealand's Slipper Island, which comes with airstrips and houses, for $5.6 million.

A Chinese buyer paid five million yuan (now $800,000) for an island in Fiji in an online auction last year, which also saw a British island sold for four million yuan, state media reported.

"Management of private islands in other countries is more developed that China," IT consultant Grammy Leung, 31, told the owners' forum.

He paid around 500,000 yuan last year for a 1.6-hectare outcrop in lake in Canada's Nova Scotia, adding he wanted one far from the shore, with a "feeling of independence".

At the event Manuel Brinkschulte, China managing director for Hamburg-based Vladi Private Islands, handed out brochures listing havens from Asia to Europe.

"China is our fastest growing market, though not our biggest," he said, wearing a pair of dark sunglasses.

For Western buyers, purchases are "like a private treat", he added. "But in China people are looking at islands from an investment point of view".

Whipping out a smartphone, he showed off photographs of a Chinese foodstuffs magnate and his wife on an island-shopping tour of Greece earlier this year.

But the businessman shunned the sunny Mediterranean and is instead in negotiations to buy a 140-hectare Scottish island, complete with golf course and small hotel.

"They like that it's completely different from China," Brinkschulte said. "With almost no one to be seen."