Based on asymptotic analysis of a passive cable model,we derive a bilinear spatiotemporal dendritic integration rule for a pair of time-dependent synaptic inputs.Further simulations of a realistic pyramidal neuron model and electrophysiological experiments of rat hippocampal CA1 neurons verifies our rule.We demonstrate that the integration of multiple synaptic inputs can be decomposed into the sum of all possible pairwise integration with each paired integration obeying a bilinear rule.