The press ads were part of the charity's "saving children from a living death" campaign, designed to raise awareness about the effects of childhood disadvantage and to appeal for donations.
Nine people complained to the ASA, objecting that the images were offensive and extremely distressing.
One ad shows the body of a dead woman, face down, having jumped from a tall building. Next to the body are the words, "Louise Brady. Died: Age 1 month". The copy then goes on, "Born to drug-addicted parents, in many ways Louise died from the moment she was born. Nineteen pain-filled years later, high on drugs, she jumped off a building and died for real."
The ad finishes by describing the charity's work to help children and families.
Another ad shows a dead man hanging from a garage ceiling, having committed suicide. A third ad, which Barnardo's claimed has a "serenity and calmness" about it, shows the submerged body of a drowned man in a canal, while the fourth shows a battered woman's body lying face down in rubbish.
All the ads are meant to convey the idea that childhood trauma, neglect or abuse contributed to the subjects' tragic deaths years later.
Barnardo's defended the ads, saying that the children they helped faced extreme disadvantages and the campaign reflected how abuse, neglect and violence in childhood could affect later life.
Some of the ads had already been toned down following advice from the Committee of Advertising Practice. For example, the picture of the hanged man had been changed to show the man only from the thigh down.
The ASA decided that the ads were unlikely to cause distress or serious or widespread offence, and the complaints were not upheld.
The ads were created by Bartle Bogle Hegarty, and the photographs were by the Israeli-born photographer Nadav Kander who now lives in London.
BBH consulted forensic experts to ensure that the ads were as realistic as possible, and used professional stuntmen and models. The ads kicked off on June 13 and are running in the national press for eight weeks.