The 12inch ship’s bell that has been used to mark the beginning of the service at Polbeth Harwood Church every Sunday for the last five years has been taken from the inner courtyard some time between 12.30 pm on Friday and 10 am on Saturday 23 July 2011.
The shiny brass bell is thought to be worth a three-figure sum of money but is more of sentimental value to the congregation.
Lothian and Borders Police are appealing for witnesses to the theft.
A police spokesperson said: "We know whoever was responsible used a ladder to climb the outer wall at the main entrance, so we are appealing for anyone who may have been in the area at the time, and who may have seen something suspicious, to get in touch.
"This bell has been used at the church for the past four or five years, and will be sorely missed by the congregation for its sentimental value.”
Anyone with information should contact Lothian and Borders Police on 0131 311 3131, or the charity Crimestoppers on 0800 555 111.