Abstract: To evaluate the damage extent of structural members under earthquake, a method of vulnerability curves based seismic damage assessment for reinforced concrete columns is proposed, using the damage index which is based on the vertical residual capacity. By means of adopting the refined analysis model which avoids assuming RC column as the single-degree-freedom system, the vulnerability curves with lognormal distribution are constructed by incremental dynamic analysis for its damage assessment. It is demonstrated that the proposed method of damage assessment for reinforced concrete columns is simple in calculation as well as effective in evaluating the damage extent for different seismic intensity indices, and could provide theoretical evidence for safety evaluation and rehabilitation after earthquake.