This study aims to develop a Communication Enhancement Program for People with Chronic Schizophrenia (CEP-S), and to evaluate the effects of CEP-S.People with chronic schizophrenia are characterized by core communication disturbances; therefore, a program to enhance their communication skills is necessary. As such, they are predicted to have difficulty fitting into society, such as relationships with people, due to issues such as having normal communication with others. Therefore, a program to enhance their communication skills is necessary.This study used a non-equivalent groups design with pre- and post-tests. In order to make a preliminary evaluation of CEP-S, controlled clinical trial was performed by setting experimental group and control group. 20 participants were in the experimental group, and 21 participants were in the control group. Ten sessions of CSE-S were provided over 5 weeks. The data were analyzed using SAS 9.2. Data analysis used descriptive statistics, chi-square and t-tests, and ANCOVA.Statistically significant differences were found between the experimental and control groups in terms of the communication disturbance, emotional expression, empathy competence, communication competence, and interpersonal relationship skills.The program improved the communication skills of people diagnosed with chronic schizophrenia and provided evidence for the effectiveness of interventions in improving interpersonal relationship skills. The results of this study will expand mental health care professionals' knowledge of how to increase communication skills when supporting people with chronic schizophrenia.