Abstract-Medical applications of microwaves (i.e., a possibility to use microwave energy and/or microwave technique and technology for therapeutical purposes) are a quite new and very rapidly developing field. Microwave thermotherapy is being used in medicine for cancer treatment and treatment of some other diseases since early eighties. This paper is a contribution to a theory of phase array applicators to be used for a microwave thermotherapy (microwave hyperthermia) in a cancer treatment. It deals with a study and theoretical evaluation of homogeneity of SAR distribution in cylindrical agar phantom for several different values of its radius. Discussed SAR distribution is in our case created by simulations of EM field exposure done by aid of four microwave stripline type TEM mode applicators of the same type.