Invasion of erythrocytes by Plasmodium falciparum is an obligatory step in the life cycle of the parasite. A major challenge is the unambiguous identification and characterization of host receptors. Because erythrocytes lack nuclei, direct genetic analyses have been limited. In this work, we combined an in vitro erythrocyte culture system, which supports P. falciparum invasion and growth, with lentiviral transduction to knock down gene expression. We genetically demonstrate, in an isogenic background, that glycophorin A is required for efficient strain-specific parasite invasion. We establish the feasibility of in vitro systematic functional analysis of essential erythrocyte determinants of malaria and erythrocyte biology.