"I'm not saying that none of the things he wants will happen," Merkel said in an interview with ARD public television.
But the 40-year-old French leader has plans for the 19-nation eurozone "that he knows are not the right ones as far as I'm concerned," she added.
German and French ministers are set to meet later this month to find common ground on EU reform, ahead of a meeting of all EU leaders on June 28-29.
Merkel singled out Macron's hope for a jointly managed investment budget of "one or two percent of gross domestic product" in the single currency area as overambitious.
Many Germans fear ending up on the hook for debts run up by other EU members, and the chancellor last week suggested that a "limited" investment budget of a few tens of billions of euros would be enough.
Nevertheless, Merkel rejected accusations that Germany has failed to meet ambitious French proposals with a vision of its own.
EU nations' failure to speak and act with one voice abroad is a "danger", Merkel warned, as is the fact "that we have no collective approach to the question of managing migration," vital if freedom of movement within Europe's borders is to be upheld.
The German leader called for an EU-wide asylum authority and collective standards for granting or refusing applications for protection, as well as a joint border protection force.
"We need a real European border police that can act if necessary even if it displeases one of the (EU) states with external borders." Conflict over how to share the burden of asylum seekers has caused rifts in the EU, with border states like Italy and Greece complaining they are overstressed while east European nations reject any move to redistribute migrants among member countries.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)