AimTo test the hypothetical model of adherence to treatment among patients with coronary disease after percutaneous coronary intervention.DesignA descriptive, explanatory, cross‐sectional survey.MethodsThe study was conducted in 2013 with 416 patients in five hospitals in Finland. The adherence of patients with chronic disease instrument, the adherence visual analogue scale, the social support for people with coronary heart disease instrument, the EuroQoL five‐dimensional scale and EuroQoL visual analogue scale were used. The data were analysed using descriptive statistic. The hypothetical model was tested using structural equation modelling.ResultsThe hypothetical model explained 30% of perceived adherence to treatment. Structural equation modelling confirmed that motivation, support from physicians and next of kin had direct associations with adherence. Indirectly, informational support, results of care, perceived health, anxiety and depression were associated with adherence. The background variables associated with adherence were gender, relationship, physical activity, consumption of vegetables and consumption of alcohol.