This paper presents experimental validations of our proposed wearable system for photoplethysmography (PPG) on cervical body surface. PPG is a non-invasive optical technique, that makes it possible to analysis characteristics of cardiovascular diseases diagnose on body surface. We have proposed PPG sensor where the green LED and the PD are placed, that mounted on cervical body surface to detect of the PPG on account of him/her with non-restriction. In this study, we aim to consider the efficacy of our proposed wearable system by evaluating a pulse wave velocity (PWV) calculated from a pulse transit time (PTT) between two organs that is a diagnostic index of arteriosclerosis. In this paper, first, we describe an estimation method of the PWV. Then, our proposed wearable system is evaluated the efficacy by comparison with reference data by a conventional method. Finally, verification for mean blood pressure calculated by the measured PWV data is discussed.