The ability of precisely determining the age of fish is essential for surveying fish ecological traits and fish conservation. In this study, we compared the readability and consistency of age readings, which obtained from three calcified structures (otolith, dorsal spine and anal scale) of Gymnocypris eckloni from the upper reaches of the Yellow River, China, and established a discrimination equation to age the lowage individuals. The readability ranked in a descending order of otoliths > dorsal spines > anal scales. The maximum ages assigned by the otolith, dorsal spine and anal scale were 25, 17 and 16, respectively. Results indicated that dorsal spine was optimal for the individuals aged 6 or less, while otolith was the most suitable structure for those aged 7 or greater. All the samples aged 6 or less were clustered by total length, weight, length and somatic weight. With stepwise discriminant analysis method, total length and weight with significant discrimination ability were selected to establish a discriminant function. The statistical results showed that 88.90% of original grouped cases were correctly classified, and 88.40% of crossvalidated grouped cases were correctly classified, indicating that G. eckloni aged 6 or less could be directly aged by discriminant analysis of total length and weight, with total length ranging from 93 to 259 mm and weight ranging from 6.25 to 177.10 g.