Objective This study is aimed to validate whether Chinese rare minnows (Gobiocypris rarus) are applicable for the juvenile fish growth test as a test fish, and to lay a foundation for the national standards of chemical testing. Methods According to “OECD Guidelines for the Testing of Chemicals No. 215: Fish, Juvenile Growth Test”, juvenile fish growth tests were performed using G. rarus that were exposed to two reference substances ( potassium bichromate and 3,4?dichloroaniline). To evaluate the repeatability of the testing method using G. rarus, the toxic effects of each substance were determined three times in our testing facility, while other domestic laboratories were involved in the ring test program to evaluate the reproducibility of the method. Results Regarding the repeated tests, the mean estimates of the concentration that would cause a 20% reduction in growth relative to controls (EC₂₀ ) were 30. 9 mg/ L and 163 μg/L for potassium bichromate and 3,4?dichloroaniline, respectively. For both, the coefficients of variance were < 15%.Although higher coefficients of variance for the datasets of the two substances were reported in the ring test, EC₂₀ values from all laboratories varied within a range of (x ± 2s). Conclusions Evaluating the repeatability and reproducibility of this test using G. rarus has presented promising result, and the level of sensitivity of this native fish species is comparable to that of Oncorhynchus mykiss in relation to the exposure of 3,4?dichloroaniline. Therefore, G. rarus can serve as standard test fish for toxicity studies.