The Mexican government says 15,273 people were killed last year in violence related to drug trafficking.
The total makes 2010 the most violent in Mexico's recent history.
Most of the dead were the result of a turf war between Mexican drug cartels.
President Felipe Calderon acknowledged that 2010 had been "a year of extreme violence". However, the murder rate dropped by 10% in the fourth quarter of the year.
Half of the murders were in three northern states: Chihuahua, Tamaulipas and Sinaloa where rival drug gangs are battling for control.
A government spokesman said other states had been virtually untouched by the violence.
The BBC reports the figures include the killings of gang members, police and troops, as well as innocent bystanders.
The number of drug-related killings for the past four years now totals 34,612 people.
The BBC reports previous government figures issued last month put the total number of dead at 30,196.
