Police, paramedics and the coastguard attended the scene shortly after 4.30pm on Tuesday.
The woman's condition was stabilised for 90 minutes before she was taken by ambulance to Blackpool Victoria Hospital.
A spokesman for North West Ambulance Service added: “We responded with an ambulance, a critical care paramedic team, an advanced paramedic, and an operational commander.
“A woman in her 50s received initial treatment for her injuries before being extricated and taken to the hospital.”
Onlookers said it looked as though she had fallen through a ‘trap door’ in the boards close to the café.
Crowds of shocked onlookers ran to the woman’s aid and alerted emergency services.
Central Pier was evacuated and a cordon was put in place under the pier as the incident was investigated.
The arcade at the front of the pier reopened at around 6pm. The Terrace Bar was unaffected by the incident.
It is unclear if the incident will now be investigated by Blackpool Council’s health and safety department or by the Health and Safety Executive.
The Blackpool Pier Company, which runs Central Pier, has been contacted for comment as well as Blackpool Council.
1. Central Pier was evacuated and closed after a teen fell through the boards to the beach below
Central Pier was evacuated and closed after a teen fell through the boards to the beach below | nw Photo: nw
2. Central Pier was evacuated and closed after a teen fell through the boards to the beach below
Central Pier was evacuated and closed after a teen fell through the boards to the beach below | nw Photo: nw
3. Crowds below Central Pier in Blackpool trying to help teen who fell onto the beach through boards above
Crowds below Central Pier in Blackpool trying to help teen who fell onto the beach through boards above | Blackpool Voice Photo: Blackpool Voice
4. Investigators below Central Pier in Blackpool after a woman falls through boards to the beach
Investigators below Central Pier in Blackpool after a woman falls through boards to the beach | NW Photo: NW
5. Investigators below Central Pier in Blackpool after a woman falls through boards to the beach
Investigators below Central Pier in Blackpool after a woman falls through boards to the beach | nw Photo: nw
6. Emergency service below Central Pier after teen fell through boards to the beach
Emergency service below Central Pier after teen fell through boards to the beach | Blackpool Voice Photo: Blackpool Voice