Malnutrition is common in patients with head and neck cancer due to cancer cachexia, anti-cancer therapies, impairment in food intake due to the tumor etc. This study aims at studying the effect of diet counseling intervention on dietary intake and anthropometric indices. Experimental design with only one experimental group was conducted on 14 head and neck cancer patients who were admitted for chemo-radiotherapy. Detailed assessment of anthropometry and diet was done in the before, during and after the diet counseling intervention of 7 weeks. There was mean weight improvement of 2 kg (p<0.001) during the intervention period that can be attributed to a significant increase in the dietary intake of energy (p=0.034), protein (p=0.011), calcium (p<0.001), zinc (p=0.041), vitamin C (p=0.046) and vitamin A (p=0.019). However there was no statistically significant improvement in the mid-upper arm circumference (MUAC). This increase may be a sign of improvement of nutritional status as normally cancer patients tend to show a decrease in MUAC. This indicates the success of the diet counseling intervention. An even greater improvement in these parameters can be achieved if intervention is provided before the initiation of chemoradiotherapy and has to be continued even after the therapy is complete.