This paper proposes protection schemes for closed loop distribution networks with distributed generators. Generally， most distribution networks operate in radial or open loop configurations due to the security requirements and protection limits. With the rapid expansion of modern power systems and the demand for high quality power supplies， the closed loop operation is being gradually adopted. Furthermore， with the increasing penetration of distributed generators， radial operation is not compatible with improving system stability with distributed generators. This paper investigates the protection requirements of the closed loop network， and analyzes the characteristics of conventional protection schemes applied to closed loop distribution networks. Taking distributed generators into consideration， the paper proposes a pilot wire instantaneous protection scheme for closed loop networks. Furthermore， the possibility of non-communication over-current protection is also investigated for its potential application in closed loop networks. The proposed protection schemes show that they can significantly improve the reliability and security of closed loop distribution networks with distributed generators.