Background: Cancer is the second most serious health problem and the second leading cause of death in human. Now a days the cancer patient face physical, social and emotional issues. These have many problems in that most people have stress, anxiety and depression occasion for most people. Progressive Muscle Relaxation Technique is a relaxation exercises, you tense up particular muscles and then relax them, then you practice this technique consistently to reducing muscle tension were used to reduce the stress, anxiety depression, pain among the patient and normal people. Aims & objectives: The aim of this study was to determine the impact of progressive muscle relaxation technique on the levels of stress, anxiety and depression among the cancer patients. Methodology: A quasi-experimental study was conducted at the Puducherry Cancer Trust Hospital & Research Centre, Puducherry. Totally 60 Cancer patients who undergoing treatment were taken for the study. Progressive muscle relaxation technique was given to cancer patient. The pretest and posttest level of stress, anxiety and depression were measured using Depression, Anxiety Stress Scales - 21 (DASS-21). The data analysis done by the Descriptive and inferential statistics. & Results: At the end of the study, 100% of the patients were completed the study respectively. The study result shows that there were significant improvements in anxiety, stress and depression (p<0.001) of the cancer patient those receiving progressive muscle relaxation technique. It indicate that there was a effectiveness in the level of stress, anxiety and depression in the cancer patient. Conclusions: The improvement in stress, anxiety and depression showed the potential of PMRT in the management of cancer patients. Future studies should be carried out over a longer duration to provide stronger evidence for the introduction of relaxation therapy among cancer patients as a coping strategy to improve their stress, anxiety and depression.