Patricia Armstrong was born in Sydney and educated at Loretto Convent, Kirribilli, Queens Gate College, London and Seaforth Technical College. She has worked as an administrative assistant at the NSW branch of the ALP, a travel consultant at Mary Rossi Travel and research officer for Senator Kerry Sibraa.
Patricia Armstrong was active in a range of environmental community issues, including the preservation of bushland in Beacon Hill and improvement in the condition of Narrabeen Lagoon.