Detective Senior Sergeant Clifford Clark, of the national cybercrime centre, told Fairfax police approached Trade Me for information when there was a direct connection between a crime and the site.
"If we are talking about the unusual situations, we follow lines of inquiry and will only ask for information if there is a Trade Me link."
A police spokeswoman said Trade Me and other sites were just one source of potential information for police when investigating a crime, or attempting to prevent one.
The increase in police requests reflected the general increase in internet activity and the popularity of online shopping sites, she said. "Unfortunately [the sites are] also used by offenders."
Trade Me said the company received requests from the SIS, police and government agencies under the Privacy Act 1993.
Fairfax reported the number of inquiries to Trade Me were up by 222, to a record 3004.
Just 26 of those came from Inland Revenue Department, which came under fire earlier this year for asking Trade Me to supply it with details of more than 44,000 traders.