We evaluated the performance of a new simple formula (NSF) for the screening of hypertension by American Academy of Pediatrics Guidelines 2017 (AAPG2017) in children with overweight/obesity (OW/OB). The performance of the NSF and the modified blood pressure to height ratio (MBPHR3) thresholds against AAPG2017 was evaluated; both methods were also compared to assess the association with concentric left ventricular hypertrophy (cLVH). The study included 3259 OW/OB children (5-13 years). Two centers served as learning sample (LS) (n = 1428), four centers served as validation sample (VS) (n = 1831), and the echocardiographic evaluation was available in 409 children in VS. The NSF was [1.5 × systolic blood pressure (mmHg) + diastolic blood pressure (mmHg)] - [(26 × height (m)] - age (years). A cut-off of the NSF ≥ 193 mmHg showed sensitivity, specificity, positive, and negative predictive values of 0.92, 0.93, 0.83, and 0.97, respectively, versus the standard procedure. Against AAPG2017, the NSF showed higher specificity and positive predictive values than the MBPHR3 thresholds. Among hypertensive children defined by AAPG2017, NSF, or MBPHR3, the odds ratio (95%CI) for cLVH was respectively 1.73 (1.06-2.83), 1.69 (1.05-2.75), and 1.18 (0.75-1.85).Conclusions: The NSF shows a very high performance for the screening of OW/OB children at risk of hypertension and cLVH. What is Known: • The American Academy of Pediatrics released updated guidelines (AAPG 2017) to classify hypertension (HTN) in children. • The process needs categorization of height percentiles and comparison of blood pressure versus gender and age-adjusted values. What is New: • A user-friendly formula built on the AAPG 2017 was validated for the categorization of HTN in children with overweight/obesity. • The formula showed high performance in identifying children with HTN versus the standard procedure (sensitivity 0.92, specificity 0.93) and similar ability in identifying hypertensive children with concentric left ventricular hypertrophy versus the standard procedure (40% and 39% respectively).