We report two cases of invasive zygomycoses occurring in severely immunocompromised patients with haematological malignancies that were successfully treated with liposomal amphotericin B and surgical debridement, followed by oral administration of posaconazole. These cases demonstrated that an early instituted, aggressive and combined therapeutic approach results in a recovery from invasive fungal infection, without any relapse of infection, thanks to secondary prophylaxis using posaconazole.