Freedom of information requests for data were made by the charity and they found that the number of arrests in Lincolnshire dropped from 1,911 in 2011 to 990 in 2014.
The figures confirm the continued success of a long-running Howard League programme of work to keep as many children as possible out of the criminal justice system.
Several police services have reviewed their arrest procedures and policies as a result of the Howard League’s engagement with them.
Across England and Wales, police made 245,763 arrests of children aged 17 and under during 2010. That number has fallen every year since.
There were 112,037 arrests during 2014, of which boys accounted for 83 per cent and girls accounted for 17 per cent.
The sharp reduction in arrests has led to a significant fall in the number of children in prison which is down by 56 per cent since January 2010.
Frances Crook, Chief Executive of the Howard League for Penal Reform, said: “The Howard League has worked closely with police forces round the country to stem the flow of children being sucked into the criminal justice system
“The fantastic success of our programme of work and the police improvement to their practices means that thousands of children have not had their life chances blighted.
“It is for parents and schools to deal with normal childish challenging behaviour, not the police
“It is to the credit of the police that they have introduced restorative approaches and given front line officers discretion to make professional decisions.”