The British Agencies for Adoption and Fostering said they were "appalled" at the toy, called Kimoko the Fosterling, saying that it was "insensitive" and "hurtful" to children who had been fostered or adopted.
Children who play with Kimoko can feed her, educate her, play with her and discipline her if she is naughty. When Kimoko's IQ reaches a certain level she is adopted.
The packaging for the toy tells the child: "Kimoko was deserted at birth by both her parents. She is now in your care as your foster child. If you raise her well ... she will turn into a lovely young girl. Then she will be adopted and leave you to join her new family."
The BAAF said it had had complaints about the toy from both children and carers who had found it "very upsetting".
Its director Felicity Collier said yesterday: "The misleading messages this game gives about being in foster care are most insensitive and could actually be hurtful to children who may already have experienced some sadness.
"Children in care are among the most vulnerable in society and need all the support we can give them. It is most unhelpful when games such as this are circulating among their peers."
Ms Collier said that the idea that a certain level of IQ ensured adoption was "outrageous". She added that most children in foster care eventually return to their parents. "To assume adoption is a reward for good behaviour is outrageous.
"We urge all parents who are considering buying this toy for their children to think about the consequences for other children."Reuse content