Traffic International, a network in Cambridge, England, that monitors wildlife trade, discovered bones, claws and skins were among the most common tiger parts seized by officials, the BBC reported Tuesday.
The network said the illegal trade continues unabated despite efforts to protect the big cats.
Worldwide tiger populations have dropped in the past century from about 100,000 to an estimated 3,500, the BBC reported.
Tigers have been listed as an endangered species since October 1987, meaning all commercial trade in tigers or their parts is illegal.
The study used data from 11 of the 13 countries to which the tigers are indigenous and estimated 1,069 to 1,220 tigers were killed for their body parts..
The number of killed animals was based on analysis of 481 official seizures. More than 275 of the seizures occurred in India.
"Given half the world's tigers live in India, it's no real surprise the country has the highest number of seizures," study co-author Pauline Verheij said.
"While a high number of seizures could indicate high levels of trade or effective enforcement work, or a combination of both, it does highlight the nation's tigers are facing severe poaching pressure."