Current evaluation methods for bridge technical condition often fail to reflect the fuzziness and stochasticity during the evaluation process, so the Cloud Barycenter Theory and the deterioration model are introduced to conquer the shortcomings. The cloud models of every hierarchy and every member are built respectively based on the Cloud Partition Method, and the bridge technical condition are divided into five clouds. The evaluation method based on the Cloud Barycenter Theory is developed and the deterioration model of bridge technical condition is obtained. Detailed technical condition evaluation is conducted on the Nanning Bridge by the proposed evaluation methods based on Cloud Barycenter Theory and current standards, respectively. The study results show that the final condition grade evaluated by the proposed method by this thesis agrees well with the method provided in current standards. However, the biggest difference is that the model built herein gives consideration to the fuzziness and randomness during the evaluation process, which shows high reliability and wide applicability of the proposed bridge technical condition assessment method.