Background: Schizophrenia is a severe, chronic, and long-term mental disorder; as well paranoid schizophrenia is the most common type of schizophrenia. Activity therapy can alleviate the symptoms of mental disorders, specifically paranoid schizophrenia, by improving the patient's symptoms and quality of life. Aimed to evaluate the effect of activity therapy on symptoms and quality of life among patients with paranoid schizophrenia. Subjects and Method: Design: A quasi-experimental design (pre/posttest single group type) was applied. Setting: The study was conducted in inpatient wards at the Shebin Elkom Psychiatric and Mental Health Hospital in Meet-khalf at Menoufia affiliated with the Ministry of Health and Population, Egypt, from the beginning of August 2022 to the end of November 2022. The therapy involved 9 sessions. Subjects: A purposive sample of fifty-one patients with paranoid schizophrenia. Tools: Personal characteristics and medical history sheet, Positive and Negative Syndrome Scale (PANSS), and the Quality-of-Life Scale were used for data collection. The Results: There was a highly significant reduction in symptoms after activity therapy. As well, there was a highly significant improvement in quality-of-life after activity therapy at (p≤0.000). Conclusion: Regular activity therapy can alleviate the symptoms of patients with Paranoid Schizophrenics, which in turn improves all dimensions of their quality of life. Recommendations: Activity therapy should be provided as an intervention for patients with mental illness to improve their symptoms and quality of life.