Abstract: On assumption that simultaneous interpreting(SI) can be viewed as a vehicle which enables interactions ranging from international to intra-social spheres,high standards of quality needs to be ensured in any of its professional domains.Since there are numerous reasons for substandard interpreting performance,this paper is mainly devoted to the research of one aspect: Hesitation in SI.Based on a selective review of literatures and findings from experiments,the essay gives some clues to the causes of hesitation,and whether it can be taken as an interpreting strategy or not.