Based on a method combining the LC-MS/MS molecular networking strategy with the conventional means of phytochemical research, the chemical constituents and the availability of Paris tengchongensis, a new species found in 2017 from Yunnan Province, were investigated for the first time. The molecular networking showed that this species contained the characteristic steroidal glycosides of the genus Paris by comparison of those of Paris polyphylla var. yunnanensis. Furthermore, the detailed investigation on the 80% EtOH extract of its rhizomes resulted to the isolation of twenty steroidal glycosides including three new spirostane-type saponins, named paristengosides A-C (1-3). Their structures were confirmed by spectroscopic analyses (HRMS and NMR) and chemical methods. The new isolates were evaluated for their cytotoxicities against two human cancer cell lines (HEL and MDA-MB-231), anti-inflammatory effects on a lipopolysaccharide (LPS)-stimulated NO production model in RAW264.7 macrophages, anti-AChE, and antimicrobial activities. The results from the molecular networking and the investigation on the chemical constituents suggested that P. tengchongensis can be used as a potential resource of Rhizoma Paridis.