Background: Potentially every aspect of life in cancer patients is found to be accompanied by a mental illness of anxiety and depression that affects the Physical relationships, Psychological wellbeing, Social relationships and the Environmental domain thereby reducing the QOL of cancer patients significantly. The advancements in cancer treatment have led to marked improvement in the survival rates of cancer patients; however, distressing symptoms of anxiety and depression arising due to treatment modalities are yet to be endured. The proposed study is considered valuable since it emphasized on the quality of life of cancer patients during their treatment for cancer symptoms as one of the possible outcomes. Because patients are the best source of information for QOL data, therefore inpatients for chemotherapy treatment and outpatients for radiotherapy treatment were recruited in the study to obtain a unique perspective on how QOL is defined, assessed, and perceived with respect to anxiety and depression during the treatment sessions. Objectives: The present study was conducted to assess the association and correlation of Anxiety and Depression with the domains of Quality of Life of cancer patients during inpatient Chemotherapy sessions or outpatient Radiotherapy sessions. The primary objective was to analyze the anxiety and depression levels (Recognition patterns) with their impact on QOL of cancer patients during chemotherapy or radiotherapy sessions. Methods: It was a Psychological intervention, non-experimental, cross-sectional, descriptive, observational, hospital-based evaluation study. The Research study was conducted at Medical and Radiation Oncology department of Dr. B.L. Kapur Memorial Hospital, New Delhi, India with total duration of 5 months (December 2015-April 2016). A convenient sample of 60 patients undergoing cancer treatment was selected in which 30 cancer patients were on chemotherapy (CT Group) and the other 30 cancer patients were on radiotherapy (RT Group). Data collection was performed by using 3 validated Psychological interventional tools: WHOQOL-Bref Questionnaire, Zung Self-Rating Anxiety scale (ZSAS) and Zung Self-Rating Depression scale (ZSDS). Appropriate statistical tests by using SPSS v.17 software were utilized to determine the significant association of anxiety and depression with QOL domains. Results: As a result, it was observed that 21(35%) males [6(20%) in Chemotherapy group and 15(50%) in Radiotherapy group] and 39(65%) females [24(80%) in Chemotherapy group and 15(50%) in Radiotherapy group] participated in the research study. Majority of the patients 32(53.34%) were found to be in the age range of 46-60 years. Out of the enrolled subjects, 33(55%) were undergoing Breast cancer treatment, 6(10%) were undergoing Head cancer treatment, and 21(35%) were undergoing Neck cancer treatment. Anxiety affected the Physical domain (p=0.007), and Environmental domain (p=0.036) in the Chemotherapy group; and Social domain (p=0.016) in the Radiotherapy group. On the other hand, Depression...