Abstract: A primary goal in the design of wireless sensor networks (WSNs) is lifetime maximization, constrained by the energy capacity of batteries. By introducing in-network processing technology, data aggregation has been recently proved to be an effective method to reduce the redundant energy consumption and prolong the network lifespan. Data aggregation can also improve the data accuracy and reliability. When applying specific aggregation schemes to reality, it is necessary to take into account the aggregation time factor, whose increase will improve the aggregation efficacy but deteriorate network transmission performance. And how to allocate the entire delay-time along each route to attain a balance between these two factors is significant. In this paper, a novel aggregate contribution based delay-time allocation algorithm (ACDA) is proposed, in which the impact on aggregation efficacy of different positions in the route tree is quantified first, then the aggregate contribution is gradually refined through an iterative update process, and finally the aggregation time of every node at sink is proportionally allocated. Since this scheme takes into full consideration of location discrepancy and interaction between nodes, The simulation results show that the ACDA achieves a better performance in both aggregation gain and transmission real-time property when compared with other present schemes, just shown in the simulation results.