Introduction: Cardiovascular diseases (CVD) are the most common cause of death in Germany. General practitioners (GPs) have an important role in supporting patients in the prevention of CVD. The DECADE intervention was developed to encourage patients to improve self-management in order to prevent CVD, addressing both GPs and patients. This study focused on GPs attitudes towards patient activation and its relation to the level of activation on their patients, possible barriers according to lifestyle counselling and attitudes towards interprofessional consultations. Methods: Questionnaire-based cross-sectional analysis was conducted within the DECADE-cRCT. GPs attitudes to patient activation was measured by using seven items of the Clinician Support for Patient Activation Measure (CS-PAM). The degree of activation of the patients was measured by Patient Activation Measure (PAM13-D). The Barriers and attitudes towards responsibilities for lifestyle counselling were assessed using self-generated items on a 5-point Likert scale. Association between CS-PAM and PAM13-D was analysed using a linear mixed model. Results: 79/82 GPs responded. Mean CS-PAM score of GPs at baseline was 23.00 (range 13–27, max. 28). GPs reported lack of time, funding and uncertainty of the impact as main barriers to the routine implementation of lifestyle counselling. GPs see themselves as primarily responsible for conducting lifestyle counselling, but they also emphasize the importance of interprofessional cooperation. No significant correlations between CS-PAM and PAM13-D were found. Conclusion: GPs perceive patient activation as important. Most GPs reported that they already provide lifestyle counselling as part of their routine practice. Overcoming the identified barriers in GPs lifestyle counselling is a prerequisite for effective and patient-centred consultation on cardiovascular risk factors. The interprofessional collaboration advocated by GPs could relieve the burden on GPs and thus reduce these barriers. Trial registrations: The DECADE-study is registered in the German Clinical Trials Register (DRKS-ID: DRKS00025401; Trial registration date: 2021/06/21) and in the International Clinical Trials Registry Platform (ICTRP): https://trialsearch.who.int/Trial2.aspx?TrialID=DRKS00025401.