Tasmina Ahmed-Sheikh, MP for Ochil and South Perthshire, said she had passed more than 100 files of online abuse to police.
The party’s women’s and equalities officer said she had been “afraid” after receiving “horrible” letters and emails, with two perpetrators already convicted in court.
She decided to go public about the abuse days before the launch of a cross-party campaign, led by Labour’s Yvette Cooper, to challenge online trolls.
Ms Ahmed-Sheikh said: “I’ve tried to keep quiet about it and I haven’t spoken about these things until now. I do worry about the effect speaking out might have.
“But I am a mum of three girls and more people need to know about how this affects us and how you can feel demeaned.
“Many colleagues have suffered terribly abusive remarks too.
“We need to get the point across that when it reaches unacceptable levels and when there are personal attacks with sexual connotations, it becomes offensive.
“We are already facing a deficit of women, of people with disabilities, of members of the LGBTI community in public life.
“If there are already under-represented groups, how are we ever going to get them to come forward unless we tackle this?”