A multi-point supported piezoelectric force sensor was designed to measure a wide range of vector forces with variable application points. More specifically， this study focused on analyzing and predicting sensitivity variations of the force sensor at various application points to ensure precise measurements of vector forces at different loading points. The factors that cause sensitivity variations of the force sensor at different test positions were analyzed， and the relationship between the sensitivity at such points within the working surface of the force sensor and the force-electricity conversion coefficient of the force measuring unit was derived. A least-squares support vector machine （LS-SVM） prediction model was established. Verification experiments showed that this model accurately predicts sensitivity values for the force sensor at different application points， with an error below 3% compared to actual values. The LS-SVM model offers the advantages of speed， reliability， and high precision in predicting sensitivity for multi-point supported piezoelectric force sensors at various application points， indicating its efficacy in quantitatively analyzing complex variable relationships.