Death-row prisoner Shafqat Hussain, convicted of killing a child in 2004, has been hanged to death at the Karachi Central Prison.
According to the Dawn, his execution came despite appeals from international human rights campaigners that he was a minor when he was found guilty.
Shafqat was arrested and sentenced to death for the kidnapping and involuntary murder of a seven-year-old boy who lived in a Karachi apartment building where Shafqat worked as a security guard.
The hanging was postponed on four previous occasions this year.
But despite the postponements, legal challenges and intense lobbying, all his appeals for mercy were ultimately turned down.
The Pakistani government scrapped a moratorium on capital punishment in the aftermath of an attack on a school in Peshawar in December last year in which more than 150 school children and teachers were killed by the Taliban.
Since then, the authorities have hanged at least 193 convicts in jails across the country.