The church first opened in 1906 and will this Sunday recognise its history with past and present members of the congregation at its final service.

Colin Webb, a farmer and congregation member, said members of his family initially constructed the church building.

A lack of attendees and the cost of maintaining the building were the main reasons the church will close.

"There are not enough people around and not many attend church like they used to. On a good day, there are about an average of 35 people attending the church and Sunday school," Mr Webb said.

"We feel it's a rather sad day - especially when our pioneers went to a whole lot of work to build the church.

"The farms are getting bigger and there are not many people around. It is not economical for the Uniting church to run so many isolated church properties."

Valma Webb, an elder and congregation member, said the church had allowed the farming community to come together.

"The mental health of people is better if they get out of their house, talk to someone and find something to do. Some of them need a bit of help," she said.

Reverend Linley Liersch has worked with the Grass Flat Uniting Church congregation for the past eight years and will preach at the closing service on Sunday. The service starts at 11am.

Andrew Boatman, chairman of the Presbytery of Western Victoria, will attend.

"The congregation has been making very definite moves to merge with the Natimuk and Goroke congregation," Reverend Liersch said.

"The building itself has been rented for the last two years and we have began to have worship at the farms instead of the church."

The church has not been used for the past four years and the community has travelled to the houses of congregation members or the Uniting church in Natimuk for worship.

Services will continue in Natimuk after this weekend.