Existing multi-object trackers mainly apply the tracking-by-detection (TBD) paradigm and have achieved remarkable success. However, the mainstream methods execute their detection networks alone, without taking full advantage of the information derived from tracking so that the detection and tracking processes can benefit from each other. In this paper, we achieve strengthened tracking performance in complex scenarios by utilizing the rich temporal information derived from the tracking process to enhance the critical features at the current moment. Specifically, we first propose a critical feature capturing network (CFCN) for extracting receptive field adaptive discriminative features for each frame. Then, we design a temporal-aware feature aggregation module (TFAM), which is used to propagate previous critical features, thus leveraging temporal information to alleviate the detection quality degradation encountered when the visual cues decrease. Extensive experimental comparisons and analyses demonstrate the superiority and effectiveness of the proposed method on the popular and challenging MOT16, MOT17, and MOT20 benchmarks. The experimental results reveal that our tracker achieves state-of-the-art tracking performance, e.g., IDF1 of 75.2% on IDF and MOTA of 80.4% on MOT17.