N-terminal pro-brain natriuretic peptide (NT-proBNP) predicts cardiovascular events and mortality in hypertensive patients. Relationship between NT-proBNP level and left ventricular (LV) hypertrophy is well known in hypertensive patients. However, the studies investigating relationship between LV geometric patterns and serum NT-proBNP level have conflicting results and are in a limited number. The goal of the present study is to investigate relation between NT-proBNP and abnormal LV geometric patterns in untreated hypertensive patients. Measurements were obtained from 273 patients with untreated essential hypertension (mean age = 51.7 ± 5.8 years) and 44 healthy control subjects (mean age; 51.3 ± 4.7). Four different geometric patterns (NG: normal geometry; CR: concentric remodelling; EH: eccentric hypertrophy; CH: concentric hypertrophy) were determined according to LV mass index (LVMI) and relative wall thickness. NT-proBNP and other biochemical markers were measured in all subjects. The highest NT-proBNP levels were determined in the CH group compared with the control group and other geometric patterns (p < 0.05). NT-proBNP levels of all geometric patterns were higher than the control group (p < 0.05, for all). NT-proBNP levels were similar between CR and NG groups (p > 0.05). NT-proBNP was independently associated with LV geometry (β = 0.304, p = 0.003) and LVMI (β = 0.266, p = 0.007) in multiple linear regression analysis. Serum NT-proBNP level was independently associated with LVMI and LV geometry in untreated hypertensive patients with preserved ejection fraction.