OBJECTIVE: To compare the methods of LC-MS/MS and MEIA for the determination of digoxin concentrations in human plasma. METHODS: The concentration of digoxin in standard controls and samples from 50 patients were respectively determined by LC-MS/MS and MEIA methods, and the results obtained by the two methods were analyzed using paired t test. RESULTS: There was no statistical difference between the data of standard controls by LC-MS/MS and MEIA methods (P>0.05). However, the results of 50 samples from patients showed that MEIA data were significantly higher than LC-MS/MS data, there was statistically significant difference (P<0.01). CONCLUSIONS: There is considerable variation between MEIA data and practical data. Compared with the MEIA, LC-MS/MS is more suitable for clinical determination of digoxin plasma concentration.