Summary: A delayed vector-bias model for malaria transmission with incubation period in mosquitoes is studied. The delay \(\tau\) corresponds to the time necessary for a latently infected vector to become an infectious vector. We prove that the global stability is completely determined by the threshold parameter, \(R_0(\tau)\). If \(R_0(\tau) \leq 1\), the disease-free equilibrium is globally asymptotically stable. If \(R_0(\tau) > 1\) a unique endemic equilibrium exists and is globally asymptotically stable. We apply our results to Ross-MacDonald malaria models with an incubation period (extrinsic or intrinsic).