Current proposals threaten to reduce the amount of social housing in villages and hamlets across England, said the Rural Services Network.
The warning is contained in the network's response to a government consultation on reinvigorating the right-to-buy.
Rural Services Network chief executive Graham Biggs said the government consultation had recognised the need to replace any property sold.
But he added: "We find it difficult to understand how this can be achieved in rural areas without further significant refinement to the current proposals."
The network agreed with the principle that a balance had to be struck between the level of discount and having enough receipts to fund replacement homes.
But Mr Biggs said having sufficient receipts may not be enough in itself.
He said: "The opportunities also need to exist in terms of available developable land which can be developed at reasonable cost."
The Rural Services Network was skeptical about how one-to-one replacement could work in rural areas.
Without additional funding and free/discounted land, deals were unlikely to be viable. This was seen as a huge barrier to successful application in rural areas.
In terms of public land being available to make deals work, not all public sector land would necessarily be in the right place for replacement.
Mr Biggs said one of the biggest concerns raised by network members was around the criteria that would be put on replacement dwellings.
"In rural areas, replacement properties might end up being in, say, the nearest market town rather than in the village where the original property was sold."
This would exacerbate problems for low income households to remain in their original villages, said Mr Biggs.
The government would need to consider carefully the impact on rural areas.
Exceptions may be required to ensure that the sale of rural council properties did not exacerbate the significant shortage of properties in villages.
The full network response can be downloaded here.