Eimeria tenella is an obligate intracellular parasite responsible for avian coccidiosis. As for other apicomplexan parasites, cell invasion and intracellular development are based on apical organelles content discharge, named micronemes and rhoptries (ROP). Some ROP kinases (ROPK) are key virulence factors that hijack host cell signalling pathways. To date, among the 28 ropk encoded by E. tenella, only two proteins, EtROP1 et EtROP2, were identified at the sporozoite, the first infectious stage. We previously shown that EtROP1 was implicated in the inhibition of the host cell apoptosis by interacting with the cellular p53. Here, we functionally described the second ROPK expressed at the sporozoite stage in E. tenella. EtROP2 is an active kinase that phosphorylates cell substrates of approximately 50 kDa. Overexpression of EtROP2 by E. tenella modifies the first schizogony (asexual multiplication of the sporozoite) and reduces the prepatent period from 7 to 5,5 days. Molecular mechanism was investigated in transfected HEK293T cells, and may involve the activation of p38 MAPK signalling pathway, resulting in the overexpression of cFos transcription factor. Interestingly, cFos has already been described in E. tenella intracellular development. Collectively our results support the importance of EtROP2 in E. tenella life cycle and constitutes a new target for the development of highly specific therapeutics against coccidiosis.