Putin, during a news conference, said he needed to read the language concerning the adoption ban before making a final decision and most U.S. adoptive parents are "honest and decent people," The New York Times reported.
However, he also criticized U.S. officials, saying they allowed child abusers to go unpunished and thwarted Russia's attempts to monitor court action in such cases.
He also was critical of a law President Obama signed last week that punishes Russian citizens accused of human rights violations and for which the Russian legislation is a response. He said the U.S. law was presented by officials who still have a Cold War-era mentality.
"They just cannot do without it," he said. "They are trying to stay in the past. This is very bad and it poisons our relations."
The Magnitsky Act is named for Sergei L. Magnitsky, a Russian lawyer arrested after trying to expose a government tax fraud who died in prison in 2009.
"What are our partners in the United States worried about? About human rights in our prisons?" Putin asked. "But they themselves have many problems."
If Putin signs the adoption bill into law, it would override a bilateral agreement on international adoptions that was ratified this year. Senior Russian officials have spoken against the ban, including Foreign Minister Sergey Lavrov, who are critics of U.S. policy, the Times said.
The bill still faces two more votes before it reaches Putin.