Introduction and objective: Transient global amnesia (TGA) remains one of the most enigmatic neurological diseases. The results of latest studies indicate a strong association between acute hypertensive peaks and TGA. Elevated blood pressure (BP) is the most frequently observed clinical feature accompanying TGA. Animal studies indicate that BP peaks may lead to oxidative stress affecting mainly the CA1 sector of the hippocampus (a crucial structure for memory processing). Materials and methods: Single-centre, retrospective, cross-sectional medical records analysis of 65 patients with TGA and 64 patients with transient ischaemic attack (TIA) (control group). Analysis included systolic and diastolic BP (SBP and DBP), mean arterial pressure (MAP), pulse pressure (PP) values at admission, as well as mean and maximal circadian values of these parameters from 24-hour ambulatory blood pressure monitoring. Circadian BP variations were also assessed. Results: Patients with TGA presented significantly higher SBP, DBP, MAP and PP values at hospital admission (p < 0.05). No significant differences between both groups were found in 24-hour ambulatory blood pressure monitoring for mean and maximal SBP, mean MAP, and maximal PP. Maximal MAP and DBP were significantly lower in the TGA group. Abnormal circadian BP rhythms predominated in both groups. Regardless of circadian BP variation, SBP and PP values at admission were significantly higher in patients with TGA. Conclusions: Extremely elevated BP is related to the occurrence of TGA. These elevated values are not sustained after the end of the acute phase of TGA.