[Objective] The objective of the paper is to investigate the plant community diversity in Periglacial Landform of Mount Laotudingzi in order to provide the scientific basis for plant protection in this area. [Methods] Based on the data collected from 48 sample plots, we used species richness index and α diversity index to analyze the species diversity of the plant communities in rock stream, rock block field and rock glacier slope of Mount Laotudingzi. We also analyzed the related envitonmental factors. [Results] (1) Plant communities can be divided into 16 forest formations and 6 bushy formations belonging to 6 vegetation types which were broadleaved deciduous forest, theropencedrymion, dark coniferous forest, elfin forest, bush wood and meadow thicket. Of them, the theropencedrymion, broadleaved deciduous forest and dark coniferous forest mainly distributed in landform of rock stream; The bush wood and meadow thicket, the theropencedrymion and elfin forest mainly distributed in landform of rock block fields. The theropencedrymion, broadleaved deciduous forest, bush wood, elfin forest mainly distributed in landform of rock glacier side. Among 22 formations, some were distributed very locally, some may occur in all three habitats.(2) The value of comprehensive biodiversity index of plant community was: rock stream> rock glacier slop > rock block field; The value of biodiversity index of tree layer and shrub layer was also: rock stream> rock glacier slop > rock block field; The value of biodiversity index of herb layer was: rock block field> rock glacier slop > rock stream; (3) Species diversity was significantly different between different vegetation types;(4) Among the topographic factors, the altitude had the greatest impact on species diversity index, and the diversity index of shrub layer was the least sensitive to the elevation change. [Conclusion] The study area has relative high diversity, altitude is the dominant factor affecting the diversity pattern.