John Joseph O'Brien (February 5, 1873 – June 10, 1933) was an outfielder in Major League Baseball.

A native of Watervliet, New York, he batted left-handed and threw right-handed.

O'Brien spent part of two seasons with the Washington teams and Cleveland before moving to Boston.

What O'Brien was unique in the true meaning of the word, and had the chance of remaining so forever despite his brief and undistinguished career.

This biographical article relating to an American baseball outfielder born in the 1870s is a stub.