This was a population-based clinical trial of a polymerase chain reaction-based multiplex high-risk human papillomavirus (HR-HPV) assay using mass spectrometry (MassARRAY [Sequenom, San Diego, CA] matrix-assisted laser desorption/ionization time-of-flight mass spectrometry system [MALDI-TOF]). Participants were 10,000 women between the ages of 25 and 59 years in Guangdong Province, China (SHENCCAST II Study). All women collected a self-sample (tested with Cervista [Hologic, Marlborough, MA] and MALDI-TOF) followed by a clinician-collected cervical sample (for cytology, Hybrid Capture 2 [HC2; Qiagen, Gaithersburg, MD], Cervista, and MALDI-TOF). Patients with any abnormal result were asked to return for colposcopy and biopsies. This analysis included the data for 8,556 women. The sensitivity values for cervical intraepithelial neoplasia (CIN) 3 or worse for a direct cervical sample were 97.9%, 95.1%, and 94.3 for HC2, Cervista, and MALDI-TOF, respectively (P > .05). The sensitivity for CIN 3 or worse for a self-collected sample tested with MALDI-TOF was also 94.3%, which was similar to a clinician-obtained endocervical sample assayed with the 3 HR-HPV assays. MALDI-TOF combined with a self-collected sample provides a highly sensitive, high-throughput, low-cost-per-case assay for mass screening.