Objective To verify and compare ELISA(ELISA) and nephelometry assay for determination of residual IgA content in high concentration human Ig for i.v. injection(IVIG). Methods The two methods were verified for linear range, accuracy, reproducibility, intermediate precision and specificity, then compared. The residual IgA contents in seven batches of high concentration human were determined by the two methods, and compared with the test results by the National Institutes for Food and Drug Control. Results The IgA concentration at a range of 12. 5 ∼ 800 ng/mL, determined by ELISA, showed good linear relationship with A450(r =0. 999 96). The mean deviation of standard curve of IgA concentration at a range of 0. 261 ∼ 8. 35 mg/L by the nephelometry method was 0. 56%. The sample recovery rates of the two methods were 103. 32% and 89. 82% resp., while the RSDs of reproducibility and intermediate precision were less than 8%. The glycine as an excipient showed little interference to the determination of residual IgA content by the two methods. The determination results of residual IgA content in three batches of IVIG by the two methods showed no significant difference(P > 0. 05). However, the residual IgA contents in seven batches of high concentration human IVIG outsourced for testing were slightly lower than the determination results by the manufacturer. Conclusion Both ELISA and nephelometry assay may be used for rapid, simple and accurate determination of residual IgA content in high concentration IVIG as well as the product quality control.