ETS Related Gene (ERG) rearrangement is one of the most common genetic changes seen in roughly about 50% of prostate cancer (PCA) cases. The inhibitor of growth family member 3 (ING3) is a member of the ING tumor suppressor family. The deregulation of ING3 expression has been reported in various types of cancers. However, to date the role and function of ING3 in PCA as well as its relationship to ERG gene rearrangement has not been studied. Our initial observation from microarray expression profiling showed that ING3 was down-regulated in ERG positive prostate cancer samples in comparison to ERG negative tumors. In this work, we examined the expression and localization of ING3 in prostate cancer cell lines and tissue samples and its association to clinical outcome. We documented a significant association between ERG and ING3 and showed a significant association to the patients’ clinical outcome, thus highlighting a potential role for ING3 in prostate cancer progression.