Background: In rheumatoid arthritis care, patients and healthcare professionals regularly face health treatment decisions. Sorting out what matters to a patient as being relevant to a specific decision is therefore essential. Methods: An explorative mixed-methods study was performed to investigate patients' values for health treatment decisions and their importance in order to develop a future decision aid on value clarification. Ten semi-structured interviews with patient partners were conducted followed by an online survey among the broader population of patients. Qualitative content analysis was performed. Data from the online survey were analysed descriptively and quantitatively. Results: According to patients, 17 important health treatment decisions in rheumatoid arthritis care can occur. The most commonly reported decisions concerned the use of medication. A variety of values may guide patients' health treatment decisions. We found 66 values among four domains of values -decisional, situational, external and global. Among decisional values, reported main values were a) effectiveness of treatment on inflammation, functioning, pain and fatigue; b) avoiding negative side-effects; and c) keeping in good physical condition. In addition, situational values turned out to be a) staying independent; b) being able to meet people; and c) leading as normal a life as possible. Furthermore, patients prefer healthcare professionals who a) take comorbidity into account, b) have enough time, and c) take the patient seriously in their choicesthe external values. Finally, as global values were expressed a) autonomy; b) self-image, and c) intimacy. All values are specified by underlying quotes, for example, the value effectiveness on inflammation; "That inflammation has got to go, because you've then got the risk that you'll develop all kinds of things in the course of time". Conclusion:A variety of values may guide patients' health treatment decisions within rheumatoid arthritis care. Patients and professionals should discuss patients' values continuously.