The goal of this clinical trial is to discover the effectiveness of group-based Acceptance and Commitment Therapy (ACT) in treating depression for acute stroke patients. The main question[s] it aims to answer are:

• Group-based ACT (G-ACT) could significantly reduce the depressive symptoms in patients with acute stroke,
• the interventional efficacy could be maintained at 3-month follow-up
• similar benefits would be observed for quality of life (QOL), sleep quality, psychological flexibility, cognitive fusion, and confidence.

The patients included to the control group received usual care support in hospital, and the patients included to the intervention group received G-ACT and usual care support. the G-ACT treatment in this study comprised 7 sessions of 45-60 minutes and was administered throughout the course of the 4-week long trial.

Inclusion Criteria:

1. primary diagnosis of acute stroke, the last onset occurred within 2 weeks
2. being over 18 years old
3. scoring at least 8 on the HAMD scale
4. Be conscious and able to communicate effectively with researchers
5. Primary school education level or above, 6) having signed informed consent.

Exclusion Criteria:

1. having a history of mental illness (such as bipolar disorder) or dementia, using psychiatric drugs or sedatives within 6 months, or currently using antidepressants
2. a diagnosis of cognitive impairment
3. receiving a psychological therapy in the previous three months, or currently experiencing severe psychotic symptoms
4. a history of drug abuse or dependence