California Proposition 39 may refer to the following ballot measures:
2000 California Proposition 39, enacted by California voters to change the required supermajority vote necessary for voters to approve local school bonds. 2012 California Proposition 39, enacted by California voters to change the way out-of-state corporations calculate their income tax burdens.
See also California ballot proposition, a referendum or initiative submitted to the California electorate for a vote List of California ballot propositions