The party was not invited to take part in the Sunday Politics South programme, being filmed at the iconic Worthing landmark.
David Aherne, Green prospective parliamentary candidate for Worthing West, said: “It makes me feel very angry. It is simply not good enough for a publicly-funded broadcaster to take sides in a general election. They include UKIP in every possible programme and exclude the Green Party, even though we have more members than UKIP and are 21 years older.”
The party lodged a complaint to the BBC but the decision was not overturned.
Between 20 and 30 supporters gathered outside in a peaceful protest as the programme aired.
Paul Myers, a party member, said: “The impartiality of the BBC is at stake, here.
“We always get a positive reaction when out canvassing day-to-day and everything has been very positive.”
A BBC spokesman said the party took part in a previous debate and it tried to ensure audiences were aware of all relevant candidates.
They said: “The Green Party took part in a Sunday Politics South debate on April 19, one of four separate debates in the region throughout the general election campaign.
“Based on BBC election guidelines the parties invited to all four debates command a significantly high level of electoral support in the region, but we work hard to ensure our audiences are aware of policies from all relevant candidates in other programming.”
For a list of all candidates standing in Worthing West, click here
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