| Martin O'Brien | |
| Assembly: | Newfoundland and Labrador House of |
| Constituency Am: | Ferryland |
| Term Start: | 1976 |
| Term End: | 1977 |
| Predecessor: | Charlie Power |
| Successor: | Charlie Power |
| Party: | Liberal Party of Newfoundland and Labrador |
Martin O'Brien is a former Canadian politician who was elected to the Newfoundland and Labrador House of Assembly in the 1976 by-election. He represented the electoral district of Ferryland as a member of the Liberal Party of Newfoundland and Labrador.
O'Brien initially ran in the general election, losing to Progressive Conservative Charlie Power by eight votes; the results were later challenged in court and nullified. O'Brien then defeated Power in the ensuing by-election by a margin of nine votes, and O'Brien was seated briefly as the member for Ferryland. Power challenged the results of the election once again, alleging irregularities and another by-election was set in 1977 after the challenge was successful. O'Brien did not re-offer as a candidate in this election and Power won by a larger margin.[1]