Introduction: Investment of the US army on virtual technology in 1999 has caused this technology to become one of the major technologies in the health field. One of the important fields of applied technology is assisting patients, who cope with longlasting, painful, and stressfultroma, such as cancer. Presence of pain, depression, tension, and stress in these illnesses has caused researchers to perform extensive research in this field.

Objectives: The main purpose of this research was to determine the effect of virtual reality on mental disorders, such as anxiety, depression, and stress in people affected by cancer.

Materials and Methods: The method of the research was quasi-experimental with pretest-posttest design with a control group. The sample included all cancer cases over 12 years old, who attended Tehran research hospitals, and treatment and teaching cancer institutes, during years 2014 and 2015. The present research was a semi-experimental study with a pretest and posttest and a control group. Among the sample, 20 were cancer cases with psychological symptoms sampled with random sampling. The sample was divided to the experimental and control group. Then the experimental group played XBOX at least 15 minutes twice a week during one and a half months. At the end of this period, these 2 groups were examined through interviews and the DASS questionnaire.

Results: The result of covariance analysis indicated that using this modern technical device had a meaningful effect on reducing psychological symptoms in cancer patients.

Discussion and Conclusion: Since treatment intervention and clinical practices take place out of routine and real life of patients, such as at the hospital and care centers, in this method the therapist can do his task in a controlled virtual situation so that practices and treatment techniques are applied in a credential and proper situation with individual characteristics.