The gold medallist wants to convert part of Grade II-listed St Tewdric's House near Chepstow into reception and accommodation facilities.
But residents have said increased traffic on a minor road and late-night noise could cause problems.
The council will decide on the application next Tuesday.
Thomas married his wife Sara at the house last October and the couple have proposed adapting the stable courtyard to house new reception facilities and converting a lodge into guest accommodation.
The house would form part of the wedding venue, as well as offering further accommodation.
In a report, officers noted Mathern Community Council, which covers Thomas's home, and 33 residents had sent formal objections to the scheme.
One said: "A recently held wedding at the property was noisy with unexpected fireworks that frightened farm stock and domestic pets."
Monmouth MP David Davies also wrote and asked the council to "consider carefully" residents' concerns over a perceived negative impact on the area.
However, officers have recommended the application for approval, subject to conditions including a curfew of 1am, with music to be played inside only and to finish at midnight.
A plan by Olympic cyclist Geraint Thomas to convert his Monmouthshire home into a wedding venue has drawn dozens of complaints.