Abstract: Single well profit evaluation is one of the effective measures to reduce oil production cost.This paper explains the necessity and procedures of single well evaluation.Through input-output analysis，oil wells are divided，according to their profits，into the following four categories：negative profit wells，marginal profit wells，middle-low profit wells and high profit wells.With improvements on production techniques and management models，marginal profit wells and low profit wells can be turned into middle or high profit wells.Wells that prove to be unprofitable should be shut down.

Key words: petroleum development company, single well evaluation, profit categories, economic evaluation 