Irregular elevation is commonly formed in skin surface during dermatological diseases. Thickness is one of the parameters to assess the severity. In this research, the thickness is defined as the elevation of lesion surface from its constructed reference line which is generated by smoothing the lesion surface using moving average filter. This method is applied in dermatological disease which caused by disorder cell growth. In the clinical trial, Dermatologist classifies the thickness severity into 4 classes. The classes are divided by its thickness appearance. Dermatologist assesses 40 3D images of skin lesion taken from 16 patients. The quantitative and objective measurement of the lesions performed in this research has characterized the thickness range of each class as well as met the doctor's thickness classification. © 2009 Springer-Verlag.