Passive electric properties of biological tissues such as permittivity and conductivity are important in applied problems of electrical stimulation in studying of human electromagnetic fields interactions and development of diagnostic and therapeutic procedures. The current densities and pathways resulting from an applied electrical stimulus are dictated to a large extent by the relative permittivity and specific conductivity of biological tissues; energy absorption also depends on tissue properties. We briefly present some theoretical basis for the current conduction in biologic materials and factors affecting the measurement of tissue dielectric properties that need to be taken into account when designing the measurement procedure. Large discrepancies between the data reported by different researchers are found in the literature, which are caused by factors such as different measuring techniques used, the fact that tissue samples were taken from different species, circumstances under which the measurements were performed, and many others. Electric properties of some biological tissues are summarized and data ranges of values found for relative permittivity and specific conductivity in the literature are given. Finally, we present some applications of bioimpedance measurements.