Post-stroke hand impairments can cause functional limitations, especially in pinching and object manipulation, which negatively impact patients’ quality of life. A major concern for stroke patients is the recovery of upper extremity motor function. Objective: To trace the relationship between pinch strength and radioulnar joint positions in stroke patients. Methods: Forty-Five patients with chronic stroke with age ranged from 45 to 65 years participated in this study. Sociodemographic Data on demographic aspects were gathered carefully. The subjects were assessed while seated, the head was in mid-position with the shoulder was adducted, and medially rotated and the elbow was flexed at 90 °. The radioulnar joint was in the neutral position. The strength of the key, palmar, and tip-to-tip pinches were measured using a pinch gauge. Three trials average values were computed. Repeated measurements were taken with the radioulnar joint in supinated and pronated positions. Results: Regarding the key and the palmar strengths, the radioulnar joint neutral position showed a statistically significant difference compared to the pronation position in favor of the neutral position (p<0.001) while there was no statistically significant difference between neutral and supination positions (p<0.735 for the key strength and p<0.842 for the palmar strength). Concerning the tip-to-tip strength, the radioulnar joint neutral position showed a statistically significant difference compared to the supination position in favor of the supination position (p<0.014), and a significant difference was detected in the neutral compared to the pronation position in favor of the neutral position (p<0.001). There were significant positive correlations between the key pinch and palmar pinch, key pinch and tip-to-tip pinch, and Palmar pinch and tip-to-tip pinch with radioulnar joint positions (neutral, supination, and Pronation). Conclusion: Pinch strength after stroke is influenced by radio ulnar joint positions, with higher key strength and palmar strength when the radioulnar joint is neutral than when it is pronated. And higher tip-to-tip strength in supination than in neutral and pronation positions.