He was born on 10 July 1877 in Sheffield, Yorkshire, England to Herbert Woodruff and Mary, née Addison.
He was raised Methodist and remained active, including attending to weekly prayer meetings for students at the University of Melbourne.
He tutored in surgery there in 1898-1899 and then became a professor in veterinary science and bacteriology at the Royal Agricultural University, Cirencester, Gloucestershire, United Kingdom.
At the age of 51 in 1928, Woodruff accepted a post as director of the bacteriology department at Melbourne University when the veterinary school finally closed.
His efforts expanded the department, he influenced a number of notable scientists, and, most importantly, he established the Public Health Laboratories, now known as the Microbiological Diagnostic Unit at the Melbourne University.