In order to clarify the influence of the alternating external magnetic field on the dissolution behavior of calcium sulfate scale,ion concentration,conductivity and infrared spectroscopy were used to detect the properties of calcium sulfate scale solution,X-ray diffraction（XRD） and detecting the dissolved amount of calcium sulfate scale and other methods were used to characterize and analyze calcium sulfate scale.The results showed that the alternating external magnetic field could obviously promote the dissolution of calcium sulfate scale.Compared with the calcium sulfate scale solution without magnetic field effect,when the alternating external magnetic field was acted for 60 min,the sulfate radical mass concentration of calci-um sulfate scale dissolving solution increased from 2.41 g/L to 3.52 g/L,the conductivity increased from 5.85 mS/cm to 7.24 mS/cm,and the dissolved amount of calcium sulfate scale increased by 40%.The reason of the external alternating magnetic field promoting the dissolution was that the external alternating magnetic field could increase the percentage of hydrophilic hydroxyl groups in distilled water,and promote the molecular affinity of water molecules and calcium sulfate scale.In addition,the effect of the alternating external magnetic field also caused the crystallinity of calcium sulfate scale to decrease,and the interplanar spacing of the main crystal planes to increase,which was ultimately conducive to the contact and dissolution of scale and water.The research could provide theoretical basis for the use of alternating external magnetic fields to control the dissolution behavior of calcium sulfate scale.