Magnetically driven microrobots hold great potential to perform specific tasks more locally and less invasively in the human body. To reach the lesion area in vivo, microrobots should usually be navigated in flowing blood, which is much more complex than static liquid. Therefore, it is more challenging to design a corresponding precise control scheme. A considerable amount of work has been done regarding control of magnetic microrobots in a flow and the corresponding theories. In this paper, we review and summarize the state-of-the-art research progress concerning magnetic microrobots in blood flow, including the establishment of flow systems, dynamics modeling of motion, and control methods. In addition, current challenges and limitations are discussed. We hope this work can shed light on the efficient control of microrobots in complex flow environments and accelerate the study of microrobots for clinical use.