Background There has been a recent surge of interest in the development of the Judgement Bias Test (JBT) as a translational assay and objective measure of depressive interpretation bias. Judgement bias, namely the tendency of favoring an approach/avoidance response towards ambiguous cues, is thought to reflect a biased interpretation or anticipation of the cues. However, no study has examined the relationship between judgement bias and depressive interpretation bias. Methods We validated the JBT against established measurements of interpretation bias in a college sample (Study 1) and an adolescent sample (Study 2). Results In both samples, a negative judgement bias was significantly associated with a depressive interpretation bias. However, the strength of the associations was only moderate and failed to meet the minimum qualification of convergent validity. Conclusions Our results suggest that judgement bias and interpretation bias might be related but distinct. The JBT should not be used as an indirect assessment of interpretation bias in its current form, and it would be premature to claim that animal studies using the JBT could inform our understanding of cognitive biases in mood disorders. Nevertheless, the JBT might be useful for studying specific mechanisms, such as reward processing under ambiguity.