BACKGROUND Radial artery spasm (RAS) has been defined as one of the major disadvantage of transradial approach. OBJECTIVE The aim of this study was to investigate the predictive value of radial artery pulse grading on RAS during transradial approach. METHODS The present study prospectively included 115 consecutive patients who underwent transradial coronary catheterisation at a single centre. Patients were divided into two groups: those with RAS and those without. RESULTS The incidence of RAS was 16.5% (n = 19). Multivariate logistic regression analysis demonstrated that female sex, guiding catheter usage, and radial artery pulse grading ≤ 2 independently predicted RAS (odds ratio [OR] 8, 95% confidence interval [CI] 1.8-36.2, p = 0.007, OR 10.6, 95% CI 2.2-51.2, p = 0.03 and OR 25.8, 95% CI 6.1-108.5, p < 0.001, respec-tively). These three variables were weighted proportionally to their respective OR for RAS (female sex [1.5 points], guiding catheter usage [2 points], and radial artery pulse grading ≤ 2 [5 points]). Two risk strata were defined (low risk, score 0-4, high risk, score 5-8.5), and high risk was associated with increased incidence of RAS (n = 13 [61.9%] vs. n = 6 [6.4%], p < 0.001). CONCLUSIONS Radial artery pulse grading together with female sex and guiding catheter usage are independent predictors of RAS, and by using a simple risk score high-risk patients for RAS can be identified.