This paper has examined the fixed-time synchronization problem for delayed complex dynamic network. A new fixed-time stability lemma is derived based on some inequality techniques and mathematical induction. On the basis of the new lemma, a simple aperiodically semi-intermittent controller with less terms is introduced, and several sufficient conditions of ensuring synchronization are developed. The setting-time is only related to design parameters, network size and node dimension. Simulation examples are employed to reveal the feasibility of derived methods.