Apicomplexan parasites use two sets of specialized organelles to invade mammalian host cells, the micronemes and the rhoptries. Microneme proteins mediate adhesion and interaction with host cell surfaces and upon appropriate contact mediate discharge of rhoptry organelles. Injection of rhoptry contents into host cells prepares the host cell for invasion and intracellular replication. We discovered that host galactose-containing N-glycans are required for rhoptry discharge from the apicomplexan Toxoplasma gondii, though the corresponding interacting microneme protein was unknown. Here, we identify the parasite proteins able interact with galactose and lactose. We used agarose beads coated with lactose and galactose to precipitating the specific interactors from whole-parasite lysate. Mannose coated beads were used as a negative control due to host mannose being inconsequential in the rhoptry discharge process. The microneme proteins MIC1, MIC4, and MIC6 were identified as the primary strong interactors of both galactose and lactose. Follow up analysis confirmed their importance to rhoptry discharge and parasite invasion via their interactions with galactose-containing N-glycans. This is the first such host-parasite interaction discovered in Toxoplasma to regulate rhoptry discharge.