HIV disclosure to sexual partners facilitates joint decision-making and risk reduction strategies for safer sex behaviors, but disclosure may be impacted by depression symptoms. Disclosure is also associated with disclosure self-efficacy, which in turn may also be influenced by depressive symptoms. This study examined the relationship between depression and HIV disclosure to partners following diagnosis among men who have sex with men (MSM), mediated by disclosure self-efficacy. Newly HIV-diagnosed MSM (n=92) who reported sexual activity after diagnosis completed an assessment soon after diagnosis which measured depressive symptoms, and another assessment within 3 months of diagnosis that measured disclosure self-efficacy and disclosure. Over one-third of the sample reported elevated depressive symptoms soon after diagnosis and equal proportions (one-third each) disclosed to none, some, or all partners in the 3 months after diagnosis. Depressive symptoms were negatively associated with disclosure self-efficacy and disclosure to partners, while disclosure self-efficacy was positively associated with disclosure. Disclosure self-efficacy partially mediated the relationship between depression and disclosure, accounting for 33% of the total effect. These findings highlight the importance of addressing depression that follows diagnosis to enhance subsequent disclosure to sexual partners.