Existing works for securing network coding against wiretapping either incur high coding complexity or bring large bandwidth overhead.For exploiting the lightweight security mechanism for resource-constrained networks,an efficient secure coding scheme is proposed in conjunction with the inherent mixing characteristic of network coding.The key idea is to minimize the randomizing operations to the entire plaintext data.The proposed scheme is shown to have properties of lightweight security complexity and lower communication overhead compared with the existing traditional solutions,and can be easy in implementation and combination with classical cryptography techniques. Existing works for securing network coding against wiretapping either incur high coding complexity or bring large bandwidth overhead. For exploiting the lightweight security mechanism for resource-constrained networks, an efficient secure coding scheme is proposed in conjunction with the inherent mixing characteristic of network coding. key idea is to minimize the randomizing operations to the entire plaintext data. proposed scheme is shown to have properties of lightweight security complexity and lower communication overhead compared with the existing existing solutions, and can be easy in implementation and combination with classical cryptography techniques.