As the security key management problem is of great importance in heterogeneous wireless sensor networks (HWSN), in this paper, we concentrate on how to design an effective security key management scheme in HWSN based on the clustering strategy. HWSN is belonged a special kind of wireless sensor networks, which is made up of wireless sensors with multiple sensing attributes. Firstly, a cluster head node selecting algorithm which is organized by a rounding mode is presented. Furthermore, which sensor node is suitable to be a cluster head node is implemented by the selecting a random number for the given node in the range from 0 to 1. Secondly, the security key management process is made up of three steps, which are 1) initializing wireless sensor network, 2) establishing key and 3) updating key. Finally, a series of experiments are conducted to make performance evaluation by compared with other two schemes using the metric “resistance degree” and “number of alive nodes”. Experimental results show that the proposed scheme can manage the security key for HWSN effectivel