One of dietary alternative which can be used for overcoming thyroid dysfunction is by using Virgin Coconut Oil (VCO). The aim of this research is to know the efficacy of alternative medicine, especially VCO to improve thyroid function which can be seen from histology appearance on rat. This research is preclinical posttest only experiment with randomized control group design. The subject of this research are 25 male Spraque-Dawley strain Rattus norvegicus, 4 months and ± 300 grams body weight. Rats were divided into 5 groups : negative and positive control, and three treatment groups. Positive control group and treatment groups will given fat first until them obese. After that, the VCO is given to three treatment groups. The dosage given was conversion of human dosage, 50 ml/day, 25 ml/day and 12,5 ml/day and will be converse in the end of week. VCO given orally everyday for 28 day, after that surgical were done to the rat, then histological thyroid object are made. The observation is seen from its follicular epithel height, follicular diameter and the colloid mass on its lumen. The data was analyzed using ANOVA test continued with Tukey test. The significant result just only shown from the diameter of follicular cells. The magnificent differences were between negative control group and treatment group which get 50 ml/day of VCO; and among positive control group with in all treatment groups. Based on this research we can conclude that VCO has significant role to improved the thyroid gland activities in white rats.