Aim — to study the variations of mophometric characteristics of thrombocytes in pregnant women with hypertension disorders of different genesis. Material and methods. 140 women were examined during the third trimester of the pregnancy. There were 43 women without hypertension disorders (control group); the first group consisted of 43 women with moderate to severe pre-eclampsia; the second group — 38 women with chronic arterial hypertension (CAH), the third group — 16 patients with pre-eclampsia with underlying CAH. Clinical and anamnesis data was analyzed. Platelet morphometric parameters were determined using an ADVIA 2120i automated hematology analyzer. The following platelet parameters were evaluated: PLT (Platelet — platelet concentration), PDW (platelet volume distribution width), MPV (mean platelet volume), LargePlt (concentration of large platelet forms), MPC (mean platelet component concentration). Results. In the first and third groups with pre-eclampsia, a decrease in the number of platelets in the peripheral blood and an increase in the PDW and LargePlt indices were found. The highest MPV values were observed in group 1 (pre-eclampsia of varying severity). MPC was increased in all groups with hypertensive disorders. There was no correlation between the concentration of large platelet forms and the average concentration of platelet components, which indicates the presence of other mechanisms for regulating platelet granulocyticity. Conclusion. The data obtained can be an additional diagnostic criterion in the differential diagnosis of hypertensive disorders in pregnant women.