The rule has been in place for several years, but has been brought to mainstream attention following complaints from visitors and criticism from local entrepreneurs this season.
Several newspapers and websites have reported on the issue in recent days.
It is claimed by owners that due to the limited space within the park, it is not practical to allow people to have picnics.
A Pleasure Beach spokesman told the Blackpool Gazette: “In line with many other theme and amusement parks, guests own food and drink cannot be brought into Pleasure Beach.
“Allowances are made for guests with special dietary requirements and dedicated picnic areas are also provided for school parties booked in advance.
“Storage facilities are provided for those who bring outside food to the park.
“Guests who wish to consume food brought to the park are redirected to suitable picnic areas adjacent to Pleasure Beach.”
Re-admission is possible after leaving the park to use the picnic areas.