Human cytomegalovirus (HCMV), a member of herpes virus family, is a widespread pathogen that causes lifelong infection with sometimes fatal consequences in immune compromised individuals. HCMV dedicates a significant portion of its genome to evade the human immune system through various mechanisms to ensure productive infection. While many viruses inhibit NK cell activation by encoding immunoevasion proteins, none have been shown to interact with three domains killer cell immunoglobulin-like receptors (KIRs). Using reporter cell lines expressing individual KIRs, we screened the proteome of HCMV and discovered that a hypervariable HCMV glycoprotein interacted functionally with three-domain KIRs. Data from surface plasmon resonance and Small-angle X-ray scattering (SAXS) experiments confirm that the immune invasion protein binds directly to three domain KIRs. To further investigate the nature of this interaction, we determined the crystal structure of the immune evasion in complex with KIR3DL1. The structure revealed that the immunoevasion protein specifically interacts with the D0 domain through and induce-fit mechanism, without affecting the binding between KIR3DL1 and a canonical human leukocyte antigen (HLA) class I molecule (HLA-B*57:01). This suggests that the immunoevasion protein can transmit inhibitory signals via the D0 domain alone without involving the D1/D2 domains of KIR3DL1. These findings uncover a new strategy by which HCMV evades NK cell activity and offer insight into the evolutionary selection of D0 domain of KIRs.