Abstract: A combined analytical method based on solid phase extraction and high performance liquid chromatography(SPE-HPLC) was established for the quantitative determination of micro additive in nickel electrowinning eletrolyte,including sodium salicylate(SS) and 2,5-dimethyl-3-hexyne-2,5-diol(HD-M).Through systematic optimization of pretreatment conditions,the hydrophilic-lipophilic balanced(HLB) solid phase extraction column was selected for enrichment and purification.The optimal sample loading volumes for SS and HD-M were 100 mL and 80 mL,respectively.The solution of formic acid-acetonitrile mixture (V∶V=8∶2) and methanol-water (V∶V=8∶2) was used as eluents.C18 chromatographic column coupled with ultraviolet detector was adopted for chromatographic analysis,achieving the effective separation and detection of two additives.Under optimized conditions,SS and HD-M exhibited good linear relationships within the ranges of 0.1-10 μg/mL and 0.2-10 μg/mL,respectively.The developed method presented high sensitivity.The limits of detection(LOD) for SS and HD-M were 0.03 μg/mL and 0.06 μg/mL,and the limits of quantification(LOQ) were 0.1 μg/mL and 0.2 μg/mL,respectively.The precision and standard addition recovery tests showed that the relative standard deviations(RSD,n=5) of SS and HD-M were 3.0%-6.1%,and the recoveries ranged from 83.36% to 95.35%.The proposed method was applied to the sample analysis in nickel electrowinning workshops.Both SS and HD-M were stably detected in catholyte(circulation port and diaphragm bag),but not detected in anolyte,which was consistent with the practical process expectation.This method could effectively eliminate the interference of high-salinity matrix and was suitable for real-time monitoring of additive concentrations during nickel electrowinning production.It provided a reliable analytical basis for process parameter optimization and product quality assurance.