Abstract: Hot-rolled galvanized high hole expansion steel possesses both high formability and high corrosion resistance, which can significantly improve the service life of automotive chassis parts to meet the requirement of new energy vehicles. However, due to the addition of annealing and galvanizing processes, the precipitation behavior and changes in microstructure and mechanical properties of hot-rolled galvanized sheets are more complex compared to pickled sheets, and require further research. The effect of coiling temperature on microstructure and properties of 580 MPa grade Nb microalloying hot-rolled galvanized high hole expansion steel was studied by using optical microscope (OM), scanning electron microscope (SEM), tensile testing machine and forming testing machine. The results show that compared with high-temperature coiling at 570 ℃, the hot rolled steel produced by low-temperature coiling at 450 ℃ had relatively smaller grain size and remained more defects such as dislocations, resulting in higher energy storage. Therefore, during subsequent annealing process, the driving force for recrystallization was greater and there were more nucleation positions, making the galvanized steel has a finer grain structure. Low temperature coiling suppressed Nb precipitation during the hot rolling stage, allowing most Nb to dissolve in the ferrite matrix or be in a critical precipitation state. In the subsequent annealing and galvanizing process, more small-sized and uniformly distributed Nb-containing precipitates were obtained, which not only contributed positively to yield and tensile strength, but also significantly improved the hole expansion rate. The galvanized sheet used the hot rolled strip of coiled at 450 ℃ possessed excellent mechanical properties and local formability. Its longitudinal yield strength, tensile strength and total elongation was 503 MPa, 602 MPa and 20.5%, respectively. The average hole expansion rate reached 95%.