Previous research highlighted generation and age effects on the perceptions and uses of technology. The goal of this study was to examine the relationship between age and perceptions of a Clinical Information System (CIS) for the clinical staff (especially physicians, nurses, medical secretaries). A survey was conducted in September 2015 in a French Teaching Hospital, based on a questionnaire consisting of items on the Likert scale. As results, the impact of age has a strong impact on Perceived Ease of Use, anxiety and Self-Efficacy. The result related to Perceived Ease of Use is unexpected. Younger staff reported to be less comfortable with technology than older staff. This result is not consistent with literature. We propose an explanation consisting in the importance of clinical process and organization knowledge and skills while general technology skills of young generations may be less significant.