The NSPCC say they are concerned an increase in the number of children in care could be connected to stretched children's services being unable to manage problems effectively at home.
At the end of March, 1,964 children were being looked after by Lancashire County Council.That's up from 1,841 last year - a rise of seven per cent.
Across England, the number of children in care has seen the biggest year-on-year increase in a decade, rising by four per cent from 72,600 last year, to 75,400 this year.
A spokesperson for the NSPCC said: "Taking children into care is never an easy decision. It is therefore vital that local authorities have the resources to work effectively with families to manage any risk so children can remain safely with their families.
“Once in care, local authorities must also be able to support these children through what can be a tumultuous experience to ensure they have the best possible outcomes.”
Children can enter care for a variety of reasons, including at the request of parents if they are unable to take care of the child themselves.
Unaccompanied asylum seekers and children at significant risk of harm are also placed in care.
A looked-after child could live with foster parents or in a children's home, and the local authority has responsibility for their welfare, education and emotional wellbeing.
Children leave care automatically at 18, but the local council is required to provide support until they are 25.
They can also be returned to their parents if the court is satisfied with the arrangement, or adopted.
The number of children being adopted in Lancashire has also risen.
In 2017-18, 87 children were adopted from care, up from 73 the previous year.
Overall, adopted children made up just 13 per cent of the children leaving care this year, with the remaining leavers returning to their parents, moving into independent accommodation or going to live with court-appointed guardians.
Nationally, the number of adoptions fell by 13 per cent, from 4,370 in 2017 to 3,820 this year.
The Minister for Children and Families, Nadhim Zahawi, said: "We want every child to be in a loving, stable home that's right for them.
"In most cases, children are best looked after by their families and courts will only remove children as a last resort, when it is in the child's best interests.
"But where a child cannot live at home, we must make sure they are safe and receive the highest quality care.
"That is why we are working hard to improve the social care support for children who through no fault of their own have been dealt a difficult hand in life."