Introduction The cancer patient’s pathway is complex and involves a large number of healthcare professionals across different healthcare sectors. For most patients, the general practitioner (GP) is the first point of contact with the healthcare system when symptoms arise. However, as the patient’s pathway progresses, the GP’s role is often limited as the majority of cancer patients do not contact their GP during treatment. It has been suggested that GPs could play a more comprehensive role in the initial cancer trajectory. Aim To investigate Danish cancer patients’ evaluation of their GP’s informative and supportive role in the cancer pathway. Methods We conducted a nationwide population-based survey of Danish cancer patients’ perception of quality of care across the different healthcare sectors. A population of 8,607 patients registered with a first-time cancer diagnosis from May to August 2010 were sampled from The Danish National Registry of Patients. Of these, 6,701 were alive and could receive a postal survey during September and November 2010. In total, 4,346 (64.7%) returned the questionnaire. Results The majority of the patients reported that their first contact with the healthcare system was with their GP. Of these patients, three quarters found that the information given to them by their GP regarding upcoming procedures was sufficient. However, as treatment progressed only half of the patients found that the GP was either to some or to a greater extent sufficiently informed about their treatment and care. No differences were observed between different diagnosis regarding information from the GP and to the GP about treatment. Overall 83.2% (81.9;84.5) found, that the GP’s communicative skills were to some or greater extent good with a statistically significant difference between men and women (p<0.002). Regarding listening to their anxiety, 77.7% (76.1;79.2) found the GP good or better, again with a statistically significant difference between men and women (p<0.003).