The successful author will be taking part in a Q&A session with visitors able to buy signed copies of her novels.
This takes place between 1.30pm and 2.30pm.
All proceeds from the sale of books will be donated to Boston’s Centrepoint Outreach, a charity which helps homeless people and others in need.
Joy Ellis is a former florist turned fictional crime writer. Many of her novels are based in the Fens, where she lives with her partner – a retired police detective.
Her titles include Killer on the Fens, Darkness on the Fens, Their Lost Daughters, The Night Thief, They Disappeared, Five Bloody Hearts, The Dying Light and The Guilty Ones.
Alison Wade, library manager for GLL, said: “We are very pleased Joy Ellis has agreed to join us for Celebrate the Fens Day.
"Her books are extremely popular with library readers and feature the local landscape and places that people in Boston and the wider fen area are familiar with.
“This is first time in recent years that we have held an author event and we are really excited at the prospect.
"Boston Library is the ideal venue to promote local authors and for local people to find out more about the writing process.”
To find out more you can speak to a member of the Boston Library team, email boston.library @gll.org
Alternatively call 01522 782010.