A female Islamic teacher, who covers her face with a niqab, has urged her 18,400 Facebook followers to boycott Valentine's day, because she says the annual celebration of love was "immoral."

Umm Jamaal ud-Din, who was a Christian before she converted to Islam, is based in western Sydney and urged her followers not to participate in the annual celebration of romance.

The preacher is also known as Mouna Parkin, and has more than 18,400 Facebook followers and 430 YouTube subscribers.

View photos Sydney Muslim teacher Umm Jamaal ud-Din describes 'celebrating Valentine's Day as immoral'. Source: Ustadha Umm Jamaal ud-Din/Facebook More

She re-shared a post to her Facebook page on Monday, which used the hashtag #SayNoToValentinesDay and parodied Roses are Red-style love poems.

"Roses are red, violets are blue, celebrating Valentine's Day is what the immoral people do," she wrote on social media.

View photos The Islamic teacher used the hashtag #SayNoToValentinesDay and mocked Roses are Red-style love poems. Source: Ustadha Umm Jamaal ud-Din/Youtube More

Her words were shared beside a picture of a moral values sign in a Muslim fashion store that read: "In Islam, a woman is known to be your mother, sister, wife and your daughter. She is never known to be your girlfriend."

Valentine's Day, celebrated every year on February 14, originated as a Christian celebration to honour the third century priest Saint Valentine who was beaten, stoned, and beheaded for the crimes of marrying Christian couples.

View photos She previously told her followers it was a sin for women to pluck their eyebrows. Source: Ustadha Umm Jamaal ud-Din/Youtube More

Saint Valentine became the patron saint of love when he was executed in Rome for his faith, around 269 CE.

Ms ud-Din made headlines last September when she warned other Muslim women it was a sin to pluck their eyebrows and those who pluck should be "cursed".