Adolescents, whose parents have cancer, may manifest their distress through changes in school performance, physical complaints of pain and discomfort, as well as changes in social and interpersonal relations. In Asian’s tightly-knitted families this matter would be very severe. There has been very little research about the effects of cancer on adolescents in Iran, so the purpose of this study was to explore the Iranian adolescents’ experiences about living a parent with cancer. The present study is a quantitative part of a mixed method research with one group, pretest-posttest design. The sample of this study was 30 adolescents. A supportive-educative program was presented to them and one month later the effect of this program was examined by DASS-21 questionnaire. T-test showed that the mean of depression, stress and anxiety had significant statistical differences before and after the program’s presentation (p=0.0001). Also, before and after presenting program, there were significant statistical differences in some aspects of quality of life like physical functioning (p=.014), energy/fatigue (p=.000), emotional well-being (p=.0001), social functioning (p=.001), pain (p=.0001), general health (p=.016), subcategory of physical health (p=.0001) and subcategory of psychological health (p=.0001). Our research asserted that, in Iran because of families’ structure, the adolescents who live with parents having cancer, have many psychological problems like stress, anxiety, depression and changes in quality of life due to lack of information about cancer and support from others, therefore presenting a supportive-educative program for them could reduce these factors.