Zheng Xiaoyu headed the food and drug agency for seven years
The former head of China's State Food and Drug Administration, Zheng Xiaoyu, has been executed for corruption, the state-run Xinhua news agency reports.
He was convicted of taking 6.5m yuan ($850,000; £425,400) in bribes and of dereliction of duty at a trial in May.
The bribes were linked to sub-standard medicines, blamed for several deaths.
China has been criticised over a number of recent cases involving tainted goods, and correspondents say Zheng had become a symbol of the crisis.
Zheng had appealed against his sentence, arguing that it was "too severe" and saying he had confessed his crimes and co-operated with police.
But his appeal, heard in mid-June, was rejected shortly afterwards.
Zheng, who headed the administration from 1998 to 2005, was found guilty of accepting bribes from firms to register their products without making them undergo the necessary checks.
Following his sacking, the Chinese government announced an urgent review of about 170,000 medical licences that were awarded during his tenure at the agency.
CHINESE FOOD SCARES
May 2007 China probes reports that contaminated toothpaste was sent to the Americas
March 2007 Melamine is found in wheat gluten exports from China for use in pet food, prompting a recall of at least 100 pet food brands
Nov 2006 A dye farmers fed to ducks to make their eggs look fresher is found to contain cancer-causing properties, and 5,000 ducks are culled
August 2006 About 40 people in Beijing contract meningitis after eating partially cooked snails at a chain of restaurants
Zheng's sentence was seen as unusually harsh for such a senior figure, but the BBC's Dan Griffiths in Beijing says the government hopes the execution shows it is getting to grips with the crisis.
However, food and drug safety standards vary widely across the country and reform will be a major challenge, our correspondent adds.
At a news conference in Beijing on Tuesday, the food and drug agency admitted it had a huge job ahead to improve its supervision of safety standards.
"As a developing country, China's food and drug supervision work began late and its foundations are weak," spokeswoman Yan Jiangying said.
"Therefore, the food and drug safety situation is not something we can be optimistic about."
She said Zheng Xiaoyu's case had "brought shame" on the department, adding that anyone who abused their power would be punished.
Chinese officials have already acknowledged that the country could face social unrest and a tarnished image abroad unless improvements are made.
Dozens of people have died in China because of poor quality or fake food and drugs, sparking widespread international fears about the safety of Chinese exports.
Thirteen babies died of malnutrition in 2005 after being fed powdered milk that had no nutritional value.
US inspectors have blamed exported Chinese pet food ingredients, contaminated with melamine, for the deaths of cats and dogs in North America.
And they recently halted shipments of toothpaste from China to investigate reports that they may be contaminated with toxic chemicals.