he Hong-Kong registered owner of the NagaWorld complex, Nagacorp Ltd, has a 70-year lease on the casino and says it made a profit of $245 million mainly from its Cambodia operations in the first six months of 2019.
About 3,000 workers joined the rare walkout in front of the casino in the capital, one of around 100 casinos which have shot up -- many in the last few years to serve a flood of Chinese customers - across the kingdom, News Yahoo reports.
The company website boasts it is "one of the world's most profitable gaming companies" and enjoyed a turnover of $1.4 billion in 2018.
But workers, who earn between $190-300 a month, say the rewards have not trickled down to them.
"We are demanding a pay increase to $500 a month for casino staff and $300 for people who work in the hotel," trade unionist Chhim Sithar told AFP.
The protesters are also demanding the reinstatement of a union president who was suspended by the company in September after she tried to protect a worker's rights.
"The company made a huge profit in recent years," said Sithar, the suspended union official.
NagaCorp, which has the exclusive license to operate in Phnom Penh until 2065, is building a third casino in the capital hoping to lasso in more VIP customers from China, who beat a ban on gambling in the mainland by going on overseas junkets.
Cambodia is one of Southeast Asia's poorest countries and its citizens are officially barred from playing in the casinos.