Christian Allard was an SNP MSP for the North East of Scotland between 2013 and 2016, and is now standing to become an MEP.
Mr Allard, who has brought up his family in Scotland, said EU nationals have been “used as a bargaining chip” by the Prime Minister.
At an SNP event in Inverurie, Aberdeenshire, he will say: “EU nationals should use this election to send Theresa May a message.
“Try running our NHS without nurses and doctors from the EU. Try running our world-class universities without researchers and staff from Europe. Try running our fruit farms or our fish processors without us.
“Freedom of movement is essential to Scotland’s public services and our future prosperity.
“Scotland’s future lies in Europe. A vote for the SNP is a vote to make clear Scotland says No to Brexit.”