Officers were on patrol near the perimeter of HMP Wymott, near Leyland, at shortly before midnight yesterday (Sunday, May 10) when they spotted a Toyota CHR parked near the security fence.
As the officers approached, two people were seen running away from the car and were arrested a short time later.
A woman aged 44, from Nottinghamshire, has been arrested on suspicion of possession of a Class B drug with intent to supply.
A 16-year-old boy, from Staffordshire, has also been arrested on suspicion of possession of a Class B drug with intent to supply, as well as car theft.
Both remain in custody.
Officers recovered a quantity of drugs from the Toyota, suspected to be cannabis, as well as a drone and a number of mobile phones.
The force said "enquiries are on-going".
HM Prison Wymott is a Category C men's prison in Ulnes Walton, near Leyland.
Situated next to HMP Garth, the prison houses hundreds of sex offenders, as well as inmates sentenced for mainstream offences.