The Jianchuan picritic porphyrite consists predominantly of olivine, clinopyroxene and plagioclase. In this paper, the authors determined chemical composition of clinopyroxene from the picritic porphyrite and picritic cumulate from Erlong and Manyuan areas in detail by electron microprobe analysis. The results show that most clinopyroxenes in Jianchuan area are composed of augite,which contains relatively low TiO₂(0.62%～2.84%), Al₂O₃(1.86%～5.15%) and Na₂O(0.23%～0.61%). Compared with those in the matrix, clinopyxenes of phenocrysts from Erlong and Manyuan areas are enriched in more magnesium but have poorer iron. The parental magma of the Jianchuan picritic porphyrite should belong to tholeiitic series, characterized by low alkali content, high CaO content and very low oxygen fugacity. During the formation of the clinopyroxene, cationic isomorphic substitution commonly occurs, and the main equations are Mg+Si=Al^Ⅳ + Al^Ⅵ and Mg+Si=Al^Ⅳ+Fe³⁺, in which Ti and Na tend to be incorporated into the titanic augite. The crystallization temperature and pressure of clinopyroxene in Jianchuan picritic porphyrite were estimated by the clinopyroxene_melt equilibrium. The results show that the crystallization temperature (1 324～1?428℃) and pressure (1.5～2.9 GPa) of clinopyroxenes in Erlong and Manyuan picritic porphyrite were predominantly lower than the crystallization temperature (1?439～1 462℃) and pressure (3.0～3.2 GPa) of clinopyroxenes in Manyuan picritic cumulate, and the formation depth of clinopyroxene in Manyuan picritic cumulate might have been larger than that in Erlong and Manyuan picritic porphyrite. Generally, the formation temperature and pressure of the Jianchuan picritic porphyrite were high, suggesting the derivation of materials from a relatively great depth. One possibility is that the rocks were formed by partial melting of lithospheric mantle resulting from upwelling of asthenosphere along the deep faults, whereas the other possibility is the involvement of mantle plume,i.e., the Permian Emeishan mantle plume was reactivated, probably resulting in large_scale magmatic activities. The evidence is as follows: the temperature of the clinopyroxene in Jianchuan picritic porphyrite is moderately higher than that of asthenosphere and the clinopyroxene in Lijiang picrite; the Mg^# both in bulk_rock and in clinopyroxene of Jianchuan picritic porphyrite is close to that in Lijiang picrite, suggesting that Jianchuan picritic porphyrite might have shared a common source region with the Lijiang picrite, or the characteristics of their sources were largely inherited from the Permian plume.