Surgery for pheochromocytoma and paraganglioma (PPGL) can lead to life-threatening complications, such as intraoperative hypertensive crises, even when adequate doses of preoperative α-receptor blockades are administered. The aim of this study was to identify preoperative factors associated with maximum arterial pressure (AP) during surgery in patients with PPGL. We retrospectively reviewed the cases of 61 PPGL patients who underwent surgical resection in our hospital between 2006 and 2020. The primary outcome was intraoperative maximum AP as a single index for continuous variables. The normal distribution of the results was confirmed by the Kolmogorov–Smirnov test. Simple and multiple linear regression model were used for statistical analysis. The median maximum systolic AP during surgery was 165 mmHg (interquartile range: 150–180 mmHg). Although the 24-h urinary-fractionated metanephrine (MN) and normetanephrine (NMN) (mg/day) was not normally distributed, the logarithmic representation (base = 10) of the combination of these continuous variables showed a normal distribution (p = 0.549). Log24 − h urinary−fractionated MN and NMN was correlated with intraoperative maximum AP (R = 0.481, p < 0.001). Multiple regression analyses showed that diabetes mellitus (β = 15.835, standard error [SE] = 7.550, t statistic = 2.097, P = 0.040), the classic triad (β = 14.081, SE = 5.668, t statistic = 2.484, P = 0.016), and log24 − h urinary−fractionated MN and NMN (β = 14.641, SE = 5.842, t statistic = 2.506, P = 0.015) were independent factors associated with intraoperative maximum AP. Patients with PPGL accompanied by diabetes mellitus, the classic triad, and high log 24−h urinary−fractionated MN and NMN values may be at risk for hypertensive crises during surgery regardless of whether preoperative α-receptor blockades are used. Clinicians should manage these patients more carefully and effectively.