Abstract: Explosion vulnerability analysis of bridge structure provides a reference for bridge design, disaster assessment and insurance evacuation. Explosion vulnerability of a typical expressway continuous bridge circular pier was analyzed to use non-parameter method in this study. An efficient numerical simulation model for bridge pier under explosive load was established, and damage feature and pier damage grade were defined. The vulnerability curve of pier under explosion load was obtained through statistics to analyze response samples of pier column under explosion load. Results show that when the explosion equivalent exceeds 200 kg, the probability of exceeding the level of slight damage to the pier has reached 1; when the explosion equivalent exceeds 300 kg, the probability of exceeding the moderate level of damage to the pier is close to 80%. The curve with damage level of 0.8 shows a continuous upward trend in the range of 0-500 kg explosive equivalent. The vulnerability curve can be used to predict the probability of various damage levels for piers at various explosion equivalents to assess the damage of the pier accurately.