Nowadays, networked control systems (NCSs) have been a popular research topic in both academia and industry areas. However, the NCSs also present great challenging problems due to imperfect communication, node moving, external interference and hacker attack. In this paper, we review some of the recent challenging researches for NCSs. Several concerned research subjects in NCSs are surveyed, including network-induced delays, packet dropouts, packet disordering, external disturbance, parameter uncertainty, data quantization, event-triggers mechanism, sensor or actuator failures, scheduling protocols, network attack and network topology. Correspondingly, various control laws to deal with these issues are discussed. Finally, some conclusions are given, and possible future directions are explored.