The service aims to attract those who are interested in heavy metal music. It has been described as a "blend of ancient and contemporary expression of worship infused with the rich imagery and sounds of heavy metal, rock and goth."
Metal Mass is being held at St Michael and All Angels Church in Bristol and is being hosted by On This Rock and Foundation, two faith arts groups from the city.
A spokesperson for On this Rock said: "We know a lot of people in the music scene who have been put off Christianity by some pretty negative and judgmental attitudes towards rock and metal.
"This event is trying to stand against that negative perception and be something different - we want to celebrate this awesome music as part of an act of creative worship. So whether you are bursting with faith, just clinging on, or have no sense of faith at all, you're very welcome."
Organisers have said they will not be playing any heavy metal music which has satanic or dark connotations, adding that there is nothing inherently sinful with the melody and musical form of the genre.
The Right Revd Mike Hill, Bishop of Bristol, will also speak at the event. Entry is free.
