**Abstract**

The dose distribution given by intensity-modulated radiotherapy (IMRT) is highly conformal, compared to conventional radiotherapies; however, due to the presence of the large numbers of fields and irregular shape and size of the treatment segments, the accuracy of IMRT delivery needs to be verified via dose measurement. Different dosimetry techniques are available that measures part of or the whole treatment immediately before a patient is treated and give us the total treatment delivery picture. But the majority of the commercially available phantoms are of homogeneous density, whereas the actual human body is a complex medium of different density patterns. Additionally, the very few heterogeneous phantoms, which are available commercially (i.e., anthropomorphic phantoms) are very costly and are not procured by most of the radiotherapy centers, especially in developing countries. Therefore, an indigenous heterogeneous phantom has been designed to verify the dose distribution prior to patient treatment.

**Keywords:** heterogeneous phantom, three dimensional conformal therapy, intensity modulated radiation therapy, multi-leaf collimator, Hounsfield unit
