Abstract: 5-Hydroxymethylfurfural(HMF) was a crucial platform compound derived from biomass. HMF had been widely applied in the synthesis of fine chemicals, liquid fuels, pharmaceutical intermediates, functional polyesters, green solvents, and other high-value products. This review focused on summarizing the main methods of preparing and the reaction mechanisms of HMF. In addition, it classified and discussed the reaction systems for HMF production from carbohydrates. At present, the reaction systems for the conversion of carbohydrates to HMF mainly included batch reaction systems and continuous flow reaction systems. Batch reaction systems could be divided into single phase, biphasic, and triphasic reaction systems, while continuous flow systems could also be segmented into single phase and biphasic flow systems. This review provided a systematic summary of the characteristics and research status of different reaction systems. The two-phase system could separate HMF in real time and reduce the formation of by-products. The addition of inorganic salts in the reaction phase could significantly improve the distribution coefficient of HMF in the two phases. The preparation system of ionic liquid or deep eutectic solvent as reaction phase had the problem of how to efficiently recycle and reuse to reduce the production cost. The continuous flow reaction system had many advantages in the preparation of HMF, but there were still some problems in the large-scale production, such as catalyst deactivation and the influence of by-products on the stability of the system. Furthermore, the review also analyzed the current challenges in this research field and outlined prospects for future development directions, in order to offer valuable insights for both basic research and industrial applications in the preparation of HMF.