The president vetoed a previous version of the legislation that congressional Democrats have deemed a top priority.
"Halloween's an appropriate day to talk about it because there's a bill moving through Congress that's disguised as a bill to help children, but I think it's really a trick on the American people," the president told attendees at the fall conference.
The State Children's Health Insurance Program, or SCHIP, the state-run, federally funded program that was set to expire September 30 but was extended at current levels until the passage of new legislation.
The president has criticized Congress, saying lawmakers are wasting time on revisions they know he will veto again.Last week's 265-142 vote in the House of Representatives was short of the two-thirds margin needed to override another Bush veto. The Senate could consider the revised bill as early as Tuesday.
"If they keep passing this legislation, I will keep vetoing it," Bush vowed, saying the latest version is even more expensive than the first, which he vetoed October 3.
The current program covers about 6 million children whose parents earn too much to qualify for Medicaid, the federal health insurance program for the poor, but who can't afford private insurance.
The new version would expand the program by nearly $35 billion over five years -- the same level as the previous bill, according to Democrats. They want to extend the program to another 4 million, paying for it with a 61-cent-per-pack increase in the federal tax on cigarettes.
"I'm going to use my veto pen to prevent" Congress from raising taxes, the president promised, saying his proposed budget increases SCHIP funding by 20 percent over five years.