Mr Salmond has come under fire both rivals and allies for joining RT which is seen as a mouthpiece of the Russian state.
First Minister Nicola Sturgeon and her Cabinet have already announced they will snub the programme because they they do not want to appear on the channel, which has been described by the US Government as “a state-run propaganda machine”.
But the Western Isles MP Angus MacNeil became the first SNP politician in office to appear on The Alex Salmond Show.
The half hour broadcast saw Mr Salmond interview Mr MacNeil, who is chairman of the Commons international trade committee, about Brexit.
SNP sources confirmed Mr MacNeil had not sought clearance from officials but said MPs can choose which programmes they appear on.
A string of high-profile figures have reportedly turned down approaches because of the channel’s association with Vladimir Putin’s regime.
Last week’s show featured Kenny MacAskill, who served as Mr Salmond’s Justice Secretary when he was First Minister.
Scottish Tory deputy leader Jackson Carlaw said: “It seems the only guests Alex Salmond can muster are old pals.
“It’s hardly the agenda-setting show he boasted it would be.”
Scottish Lib Dem MSP Alex Cole-Hamilton said: “When this show was announced I suggested that the former First Minister might want to use it to highlight the plight of some of those pushing back against the repressive Putin regime, sadly the quality of guest has been rather lower.
“Nicola Sturgeon will have her head in her hands that another SNP parliamentarian is indulging Putin’s propaganda channel.”
Mr Salmond has insisted the broadcaster will allow him “freedom of speech” and will not make editorial decisions on the show.
Last month, the First Minister said Mr Salmond’s choice of channel “would not have been my choice” and that she would have “advised him to seek another channel” if she had been asked.
An SNP spokesman said: “We consider all requests for interview on their merits as and when they come into us.”