The heterotrophic lifestyle of parasitic plants relies on the development of a haustorium, a key infectious organ required for the spoliation of host’s resources. While haustorium development in hemiparasitic plants was shown to be triggered by phenolic compounds (HIF: Haustorium Inducing Factor) derived from host roots, the induction of haustorium formation remains largely misunderstood in obligate achlorophyllous species such as Phelipanche ramosa. Recently, it was shown that the development of early haustorial structures (EHS) in P. ramosa is triggered by Brassica napus rhizospheric extracts which contain cytokinins-like molecules. We have demonstrated here, that rhizospheric extracts from host plants (B. napus, Solanum lycopersicum, Arabidopsis thaliana) contain two distinct haustorium inducing signals which synergistically increase the aggressiveness of the parasitic plant towards host plants. One of these signals contains a small group of active cytokinins constitutively exuded from the host roots. These compounds are recognized by P. ramosa histidine kinase receptors and trigger a signaling pathway involving cytokinin marker genes (PrRR5, PrCKXs) and cell differentiation genes (PrZFP6, PrTRN2). The second haustorium inducing signal contains triterpenoid-like molecules and relies on hydrogen peroxide formation. It induces a signaling pathway distinct from the cytokinin one but converging toward the same PrTRN2 signal integrator. This thus present the cue governing haustorium induction as a complex signal.