The Weston Park Foundation has written to Shropshire Council voicing its concerns over plans from the Bradford Estates to build 3,000 new homes on green belt land near Tong, off Junction 3 of the M54.
The Bradford Estates plan is currently the subject of a consultation by Shropshire Council, but was not included in the authority's own local plan.
The local plan sets out where homes can be built in the county up until 2036.
The Weston Park Foundation objection centres on the potential impact on the heritage setting of the stately home and its gardens at Weston-under-Lizard, and the knock on effect on its ability to host large functions and events – a key part of its business model.
The park hosts a number of large events such as its Camper Jam, which attracts more than 20,000 people a year, as well the Midland Game Fair, and its own events such as the popular bonfire and fireworks show.
Andrea Webster, marketing manager at the Weston Park Foundation, confirmed that the charity had submitted an objection to the plans.
She said: "We are objecting on the basis of the impact it would have on our heritage setting.
"The heritage setting of Weston Park and the broader landscape is especially important to sustaining what we do here and to the operation of the Weston Park Foundation so we can fulfil our objectives.
"Our business model is not reliant on the visitor attraction model like a lot of National Trust properties, it is wholly reliant on how we use the estate for large events like hospitality."
She added: "The other strand of our objection is based around the fact that there is no requirement in Shropshire's planning review to identify a new garden village at Junction 3 of the M54. It is not required for the development needs of Shropshire by 2036, so we as a conservation charity do not believe there are exceptional circumstances to release green belt land for development."
The Bradford Estates is run by Alexander, Viscount Newport, who is the organisation's managing director.
Weston Park was actually previously owned by the family but was gifted to the nation by current Earl of Bradford, in 1986.
The proposal for the homes has attracted considerable opposition from local residents and Wrekin MP Mark Pritchard.
Last week Mr Pritchard called on the housing minister to step in and reject the proposals.
Mr Pritchard said: "The Secretary of State and I met to discuss Shropshire Council's proposed environmental vandalism of Tong, Shifnal and Albrighton.
"What is clear is that the minister has strong powers to overthrow any out-of-touch decision Shropshire Council might be tempted to make in the future.
"The council should shelve their promotion of the site and hawking the site around the West Midlands."
Bradford Estates have argued that the proposals, which would include 50 hectares of employment land, will form a dedicated community, and contribute to prosperity in the county.
A website set up to promote the plan states: "We recognise that Shropshire is a special county and want to contribute to its future success and prosperity. We don’t just want to build homes and offices: we want to build a community which contributes to its surrounding area as much as it draws from it for inspiration."