The Pulse Transit Time (PTT) is often considered a reliable surrogate for noninvasive monitoring of blood pressure (BP) and its fluctuations. One of the primary limitations of PTT estimation accuracy is the inclusion of the pre-ejection period (PEP) artifact in the PTT signal. The second method, using dual-point photoplethysmography (PPG) to replace electrocardiogram (ECG), can eliminate the confounding PEP component and improve the accuracy of PTT estimation. However, few studies have utilized multi-point PPG for BP estimation, and the weak correlation between PTT and BP is often attributed to the lower accuracy of PTT. To address this issue, we propose a PTT acquisition method for Multi-point Photoplethysmography architecture to improve accuracy. Experimental results demonstrate a maximum PTT error of less than 1.3 ms, indicating high precision. Our approach is easy to implement and has the potential to improve the accuracy of PTT-based BP monitoring.