This paper analyzed the security threats and system flaws of present key management schemes. Combining (t,n) threshold cryptography and key management, we present a threshold key management scheme based on ECC ( Elliptic Curve Cryptosystem ). By utilizing secret key sharing and probabilistic encryption algorithm in key management, the scheme achieves threshold management of symmetric key and public key certificate, avoids the relevance between different certificates generated by the same CA (Certificate Agency) or KDC (Key Distribution Center). The scheme avoids the misuse of certificate generation and anonymity of CA/ KDC members, effectively prevents coalition attack, intruder-in-middle attack and generalized certificate forgery. Further analyses and comparison with other key management schemes also justify the scheme??s brevity, security, high efficiency, and thus considerable improvement on system efficiency regarding software and hardware application. Therefore, the scheme is most applicable to such circumstances as with restricted computation ability, integrated space and limited bandwidth yet requiring for high-speed operation.