Abstract Background Generalized anxiety disorder (GAD) is one of the most common mental disorders in primary care (PC). GAD has low remission and high relapse rates over long follow-up periods. Qualitative evidence was synthesized to understand the implementation of care and treatment options for people with GAD in PC. Methods Research published from 2008 to September 2020 was searched in five databases (MEDLINE, EMBASE, CINAHL, WOS and PsycArticles). Studies that used qualitative methods for data collection and analysis to investigate the implementation of care and treatment options for people with GAD in PC and outpatient settings were included. Non-qualitative studies, mixed methods studies that did not separately report qualitative findings and studies in languages other than English or Spanish were excluded. We used the Confidence in the Evidence from Reviews of Qualitative Research (CERQual) framework to assess the overall confidence in the findings. Results The results with a moderate level of confidence showed that the trajectory of care for people with GAD in PC and outpatient settings is long and fluctuates over time, involving multiple difficulties in accessing and maintaining initial treatment or successive treatment options. In addition, there are wide variations in the preferences for and acceptability of different treatment options. The results with a high level of confidence indicated that more information on GAD and its treatment options is needed for PC practitioners, GAD patients and their carers. The results with a low level of confidence suggested that patients use antidepressants for longer than recommended and that the interruption of treatment is not usually planned. Conclusions Initial resistance to new treatments among people with GAD can make access and adherence to treatment difficult. Improving care may require patients to be informed of possible trajectories in stepped care pathways before the initiation of treatment so they are aware that they may need to try a number of options until the most effective treatment for them is found. Increased awareness of and information materials on GAD may facilitate both appropriate diagnosis and long-term care.