Background: The importance of pharmacovigilance in Japan is gradually being recognized. However, Japanese pharmacists’ knowledge of and perspectives on pharmacovigilance have been examined only in some areas of Japan. Objective: The objective of this study was to clarify the knowledge, attitudes, and practice regarding pharmacovigilance and adverse drug reaction (ADR) reporting among hospital pharmacists in Japan. Setting: A questionnaire survey among Japanese hospital pharmacists. Method: The questionnaire was distributed to 48 028 pharmacists during a 3-month period between January and March 2017. Main Outcome Measure: The prevalence of hospital pharmacists who understood pharmacovigilance and the ADR reporting system. Results: Of the respondents (response rate; 9.9% = 4760/48 028), 21.9% were <30 years of age, 27.3% were ≥50 years of age, and 46.7% were women. In response to the question “Have you ever heard of the term ‘pharmacovigilance’?,” 12.4%, 33.8%, and 47.4% answered “I understand what it is,” “I have heard of it, but I do not understand what it is,” and “I do not know what it is,” respectively. Pharmacists who understood the term “pharmacovigilance” were also more frequently acquainted with its associated terms and actions. And, 69.7% of respondents wished to acquire more information on pharmacovigilance and 50.9% did not have a personal history of ADR reporting. The most common reason for ADR nonreporting was “It was a well-known adverse drug reaction” (44.5%). Conclusions: Our results suggest that more aggressive promotion of pharmacovigilance and of the ADR reporting system among Japanese pharmacists is needed.