ABSTRACT Objectives: the purpose of this study is to explore laypersons’ attitudes towards and experiences of medical research, and to compare them with those of physicians in Japan. Designs and Participants: fourteen Japanese adults from the general public and seven physicians participated in one of three focus interviews. Setting: Osaka, Japan. Results: trust and distrust in the physician by whom the participants were invited to participate in research played a considerable role in their decisions about participation. That the participants felt an obligation to participate was also expressed. The lay participants perceived medical research as something entirely outside of their world. A greater willingness to volunteer for research was expressed if there were direct benefits to themselves or their families. Research methods such as use of placebos, double blinds, and randomisations seemed to cause negative attitudes to medical research. All physicians were convinced of the need for medical research, including double‐blinded randomised control trials, and its significant role in medical progress. Most physicians thought that the greater awareness of the need for medical research in the community and a better understanding of the psychology of potential research participants were necessary and urgent. Conclusions: there is a good possibility that the lay public and medical professionals have sharply different beliefs about and attitudes towards every aspect of medical research. Building up a better and equal patient‐doctor relationship based on trust is a key issue in medical research, and it is mandatory to fill the gap in perception regarding medical research between them through fully informed debates.