"This law is populist and badly drafted. It will lead to the loss of 2,000 jobs," the president's office said in a statement. "In conditions of a world financial crisis, the president cannot go along with it."
The statement described the ban as unconstitutional and said it would "sharply increase the number of illegal gaming institutions."
Parliament slapped the blanket ban on gambling institutions within days of the fire which killed 10 people in central Ukraine. Officials said the hall's owners had failed to observe fundamental safety regulations.
The bill had sparked protests by casino employees, who said it would put more than 200,000 people out of work in a legitimate industry and force gambling institutions underground.
Gambling halls, many of them small and dingy have sprung up in Ukraine and other former Soviet states in the years following the 1991 collapse of communism. The law bars a variety of institutions, including casinos, halls with slot machines, bookmaking shops and internet gambling.
The president asked the chamber to suspend rather than ban gambling institutions pending passage of new legislation governing their activity. He submitted to parliament a series of proposed amendments to the bill which would enable it to take effect if the chamber approves it by a simple majority.