Lewis James O'Brien (November 28, 1868 – June 14, 1955) was a provincial level politician and medical doctor from Alberta, Canada.
[1] O'Brien remained in Germany and Austria for two years before moving back to Ontario to set up his medical practice and marry Alice John.
[1] O'Brien ran as an Independent candidate under the Unity Movement in the 1940 Alberta general election.
He defeated Social Credit incumbent MLA William Sharpe on the second count to win the Grande Prairie electoral district.
[2] O'Brien served a single term in the Assembly before announcing that he wanted to step off to the side lines and retire at a nomination convention held in the Capital Theater at Grande Prairie, Alberta on February 3, 1944.