Abstract: Research was conducted on a multi-phase group evaluation information aggregation method based on density operator. The weight of each evaluator was determined by degree of judgment dispersion and individual judgment accessing to group judgment. In addition, the multi-phase weighting vector was given through the notion of timing degree. Based on this, evaluation information was aggregated through a multi-approach. This aggregation method considered the evaluation information distribution density, which was not only at the same time but also at different times. Finally, an example is given to demonstrate the aggregation approach, and final evaluation results are analyzed.