In order to promote the convergence performance of the quantum evolutionary algorithm, a coevolutionary extended compact quantum evolutionary algorithm is proposed. Quantum chromosome can be rotated according to the multi-granularity mechanism. Chromosome crossover and mutation are based on the MPM in order to avoid loss of better pattern, and the self-adjust operation is performed in the subpopulation. Spilt and merge operation are also executed in the subpopulation and some superior individuals migrate between subpopulation, and the trait of convergence is analyzed in the paper. The proposed algorithm can reach the satisfactory solution set. Simulation results of benchmark functions and the knapsack problems show that the proposed algorithm performs well than other algorithms.