Ropetackle Arts Centre has organised a Tackle The Issues: Election Special on April 21.
The panel will include five candidates for East Worthing and Shoreham, but not Dr Carl Walker, who will be standing for the National Health Action Party.
Dr Walker said he had protested strongly to the trustees, saying he is the only candidate for the constituency to be excluded.
“It is astonishing that with the NHS promising to be a major issue at this election, and the strength of local feeling over both the fiasco of Bupa CSH and the orthopaedic services contract, and the proposed demolition of hospital buildings at Southlands, voters are to be denied the chance of hearing about the future of our health service and the implications of privatisation.”
Martin Allen, chairman of the trustees, said there were usually four people on the Tackle the Issues panel.
For the Election Special, candidates were invited for all the parties known at the time it was organised.
When Dr Walker later asked to join the panel, the trustees agreed increasing the panel would make it less effective for wide-ranging debate.
“The Electoral Commission confirmed that our decision to limit the number on the panel, based as this was on candidates representing parties with at least one current MP, was in accordance with their guidance.”
Mr Allen added: “I should emphasise that we are a community organisation, run for and by the community, and we non-political.”