After attending Glasgow School of Art, she lectured in fine art for eight years before becoming a professional writer. In the early 1970s she joined Philip Hobsbaum's writers' group, a crucible of creative activity - other members were Alasdair Gray, James Kelman and Tom Leonard.

She is one of Scotland's most popular dramatists. Her plays include Blood and Ice, Mary Queen of Scots Got Her Head Chopped Off (1987), Perfect Days (2000) and a highly acclaimed adaptation into Scots of Molière's Tartuffe (1985). Her adaptation of Euripides' Medea won the Saltire Society Scottish Book of the Year Award in 2001. Like her work for theatre, her poetry is alive with vigorous speech idioms; collections include True Confessions and New Clichés (1985), Bagpipe Muzak (1991) and Dreaming Frankenstein: and Collected Poems (1984).

In 1989, Lochhead was profiled by stv's arts series Off the Page.

As a performance artist she sets up a lively rapport with audiences, bringing to bear an impeccable sense of timing. She has made successful collaborations, notably with Dundee singer-songwriter Michael Marra. Imbued with a sense of humour that is laced with surprise and irony, her work as a whole is as thought-provoking as it is entertaining. This entertainment can be portrayed in her poem "Revelation" which compares an enraged bull to a demonic figure.