X射线双能计算机层析成像(CT)技术是安全检查领域一种重要的材料探测与识别手段。双能CT投影分解是双能CT预处理重建算法的核心内容和关键步骤。针对现有投影分解算法的不足，提出了一种基于投影匹配的双能CT投影分解算法。依据系统能谱和基材料线性衰减系数曲线，通过求解投影积分方程组建立高低能投影查找表。对于给定的高低能投影，在查找表中寻找最佳匹配点，进而获取基材料分解投影。该算法避免了现有算法复杂的迭代优化过程，简化了系统的标定过程，分解精度取决于查找表的设定步长。相对现有算法该算法有实现过程简单、易于并行计算的优点。仿真实验结果验证了算法的有效性。

X-ray dual-energy computed tomography imaging technique is an important material detection and recognition method in the field of security inspection. The projection decomposition is the nuclear content and key technique in the pre-reconstruction algorithm of dual-energy computed tomography. According to the disadvantages of the current algorithms, a projection decomposition algorithm based on projection matching is proposed. Firstly, based on energy spectrum of the system and the linear attenuation coefficient curve of the basic materials, the high-and low-energy projection lookup table can be got by solving the projection integral equations set. For a given dual-energy projection, find the best match point in the lookup table and then obtain the decomposition projection of basic materials. The proposed algorithm avoids the process of complex iteration and optimization and simplifies the process of system calibration. The decomposition accuracy depends on the step setting of lookup table. Compared to the current algorithms, the proposed algorithm′s realization is more simple and easy for parallel computation. The feasibility of the algorithm is validated by the results of simulation experiment.