Sharks take years to sexually mature, produce small litters and are exceptionally vulnerable to overfishing.
They are being caught at an average rate that is 30 percent to 60 percent higher than they can sustain, the study said.
The fish are often targeted for their fins, which are used in shark fin soup, a delicacy in Asia where a bowl of it can reportedly sell for 65 pounds, Sky News reported.
The practice known as "shark finning" - where the fish are caught and thrown back after their fins are cut off - is globally widespread, according to the researchers from Dalhousie University in Halifax, Canada.
Some areas including Europe, the US, Canada and Australia have introduced anti-finning legislation but the practice continues in most other parts of the world, they added.
Sharks are also caught accidentally by vessels looking for tuna, swordfish and other species.
The researchers, using information from nearly 100 papers, estimated global reported catches, unreported landings, discards and finning totalled 97 million fish caught in 2010.
The number is only slightly less than the estimated 100 million caught in 2000, and the 2010 figure could actually be as high as 273 million, the study said.
It is thought between 6.4 percent and 7.9 percent of all sharks are killed each year, less than the 4.9 percent that means population stability can be maintained.
Anything over that threatens the long-term survival of species like the oceanic white tip, porbeagle and several kinds of hammerheads.
"There's a staggering number of sharks being caught every year and the number is way too high considering the biology of species," study's lead researcher Boris Worm said.
The findings are published in the journal Marine Policy.