The Department of Internal Affairs says it's been advised that 46 children have been found unattended in casinos so far this year, six of them in car parks.
That compares with 101 for the whole of last year, 84 in 2010 and 34 in 2009.
The children involved were under the age of 15 and most incidents have been in Auckland.
The department says casinos are required to report the incidents to Internal Affairs, and where necessary, agencies such as the police or Child Youth and Family.
Green MP Denise Roche says the neglect will get even worse if the Government allows casinos to operate yet more pokie machines, bearing in mind that these cases are only the ones which have been reported.