Cases of parental child abduction have risen 88% in just under a decade (2003-2012), Foreign Office (FCO) figures show.
It is against the law for a parent to take a child overseas without permission from others with parental responsibility, but nearly a quarter of Britons (24%) are unaware it is a crime, the figures showed.
The FCO's child abduction section received an average of four calls a day between October 2011 and September 2012, according to the figures.
Public understanding of child abduction is also low, according to separate research commissioned by the FCO. Half the UK population thinks the Government can intervene to ensure an abducted child is returned home, the research carried out by Censuswide showed.
But the reality is that, while help is available, parental child abduction cases can take years to resolve and there is a strong possibility that the child may never be returned, the FCO said.
It is also much harder to return a child from a country that has not signed the 1980 Hague Convention, an international agreement between certain countries which aims to ensure the return of a child who has been abducted by a parent.
Daisy Organ, head of the FCO's child abduction section, said: "The increase in parental child abduction cases is a major cause for concern, particularly in the lead-up to the school holidays; we know that before or during school holidays is one of the most common times for a child to be abducted.
"We hope that this campaign will help inform and educate the UK public and encourage parents thinking of abducting their child to think twice before they cause significant distress to themselves and their family."
The FCO also pointed out that parents may suffer severe financial difficulties as they fight for custody of their child through foreign courts.
Further illustrating public misunderstanding, nearly three quarters of those surveyed (74%) thought fathers were more likely to abduct children. But, according to statistics from the Reunite International Child Abduction Centre, 70% of the charity's cases concern mothers taking the child.