Abstract: In order to investigate the impact of user recommendation on Web search behavior, the user recommendation was added to search engine results page (SERP) and observe the change of a participant behavior during Web search via eye-tracking technology. Experimental results show that the additional user recommendation does not significantly influence search efficiency, attention distribution, and click distribution. However, the participant feedbacks indicate that most of them consider user recommendation useful and refer to it during Web search. The reason of this contradiction is that participants ignore user recommendation during search process, which is inattentional blindness.