Aim To develop models for predicting the risk of target organs damage (TOD) in different phenotypes of "masked" arterial hypertension (MAH) based on methods of machine learning (ML).Material and methods A retrospective cohort analysis was performed for 284 clinical records of patients (261 males, 23 females; median age, 38 years). Group 1 included 125 patients with grade 1-2 arterial hypertension (AH) and low or moderate risk; group 2 included 159 subjects with normal "office" blood pressure (BP) exposed to chronic professional stress. The 24-h BP monitoring (24-h BPM) and ultrasound examination of the heart and carotid arteries were performed; glomerular filtration rate (GFR) was estimated using the СКD-EPI formula. MAH was phenotyped by clustering 24-h BPM data, and the risk of TOD was predicted by analysis of odd ratios (OR) and with the ML methods, random forest (RF) and artificial neural networks (ANN). Data were analyzed using the R language in the RStudio environment.Results According to results of the 24-h BPM and cluster analysis, 121 (76.1 %) subjects of group 2 had MAH. The MAH phenotypes were identified as follows: systolic-diastolic (SDMAH) (43.8 %); isolated systolic (ISMAH) (35.5 %), and isolated diastolic (IDMAH) (20.7%). As compared to stable AH, subjects with different MAH phenotypes showed both increases and decreases in individual 24-h BPM indexes. Thus, in subjects with IDMAH, mean 24-h values of systolic and diastolic BP were significantly lower than with AH while in SDMAH, they were considerably higher. The OR analysis demonstrated that odds of differently located TOD were associated with definite MAH phenotypes. With that, ISMAH was associated with the highest risk of glomerular hyperfiltration; IDMAH was associated with reduced GFR and vascular remodeling; and SDMAH was associated with left ventricular myocardial hypertrophy. The developed models for predicting the risk of TOD based on the RF and ANN methods showed a high accuracy, which was provided by multistep procedures of selecting the predictors and cross-validation.Conclusion Modern ML technologies enhance the risk stratification of patients with different clinical variants of AH.