This paper deals with a three-dimensional thermal model for landmine detection problems and an inverse problem for reconstructing the physical parameters of buried objects. Moreover, solutions are given for the estimation of the soil thermal di{\textregistered}usivity and meteorological parameters, needed for solving the inverse problem. The paper describes the main fundamental principles of thermal modelling for buried object identi¯cation and illustrates the results on data acquired from a real mine¯eld, together with qualitative and quantitative results illustrating the validity of the model.