Cancer is a disease that all human beings are afraid of it and anyone, of any age may be affected.

The objectives of this research are relationship between well-being and life expectancy in patients with cancer in Noshahr Shahid Beheshti hospital is the general purpose of this research.

Studying the relationship between happiness, general health and life expectancy of cancer patients.

The method used in this research is descriptive and correlation. Statistical population contains all the patients who were diagnosed with cancer in Shahid Beheshti hospital Noshahr. The panel sampling used as sampling method and the sample size was limited to 50 people.

In order to collect the data, we used Oxford's happiness questionnaire containing 29 multiple-choice phrases, Life expectancy questionnaire by Schneider (1991) and general health questionnaire (GHQ-28). In descriptive review of the collected data the mean, standard deviation and frequency tables were used and in inferentially section in order to determine and compare the obtained scores in these 3 tests, according to the findings, parametric methods were used.

The results show that the correlation between mental health, happiness and life expectancy was significant.

As life expectancy increases accountability; Happiness and mental health in patients with cancer increases by the same amount.