Many previous studies showed that the causal information externally given (hereafter external information) did not succeed in changing the causal structure driven from the covariation data when the external information and the covariation data were in conflict. We speculated that the salience of the external information is crucial in causal inference. The external information did not affect the causal inference when the external information and the covariation data were simultaneously presented in Experiment 1. However, when the external information and the covariation data were sequentially presented and participants were asked to report the causal structure and the strength each time in Experiments 2 and 3, participants were more likely to report the causal structure of the external information when the covariation data were drawn from a different causal structure. Results of the three experiments showed that the external information can override the covariation data under certain conditions.