The article presents reference limits of concentrations of placental growth factor and fms-similar tyrosine kinase-1 and values of their ratio in dynamics of physiologic pregnancy and in female patients with pre-eclampsy of different degree of severity in 1 and III trimesters of pregnancy. It is established that in female patients with pre-eclampsy ratio of fms-similar tyrosine kinase-1 and placental growth factor significantly exceed ratio in female patients with physiological course of pregnancy. The degree of increase of values of ration between fms-similar tyrosine kinase-1 and placental growth factor correlates with degree of severity of pre-eclampsy.