The SD-101 (Kenzmedico co. Ltd., Saitama, Japan), a non-invasive medical device capable of measuring respiratory parameters during sleep, has recently been developed. It operates while placed under the body like a bed pad equipped with 162 pressure sensors, with the patient in bed. To evaluate the efficacy and safety of the SD-101 for the diagnosis of sleep apnea syndrome (SAS), we enrolled 52 patients with suspected SAS (45 men and 7 women; mean age, 45.6 +/- 10.9 years) in this study. Each subject underwent measurement using the SD-101 and a polysomnograph simultaneously, and we analyzed and compared them. In addition, health-economic benefits of the SD-101 were estimated based on the results. A significantly strong correlation was obtained between the apnea hypopnea index of PSG and its of SD-101 (r = 0.86, p < 0.0001). No adverse event due to the SD-101 occurred, while use of the SD-101 greatly reduced "feeling of being constrained" and discomfort during examination (Wilcoxon test: p < 0.0001). These findings could indicate that the SD-101 is clinically useful and will make a contribution to health-economic benefits for SAS in Japan.