Abstract: Bsed on optical microscope and electron microprobe studies of clinopyroxenes in the basalt from Okinawa Through,we found three different generations of clinopyroxenes：phenocryst pyroxene,microphenocryst pyroxene and groundrnass pyroxene,with average size of 400μm ± ,30 μm ± and 5 μm ± ,respectively.There are obvious compositional differences among these three different pyroxene generations. From the core of phenocryst pyroxene, through microphenocryst pyroxene and the rim of phenocryst pyroxene,to groundmass pyroxene,the chemical composition evolved from Fe-rich to Mg and Ca-rich, which is opposite to the compositional evo1ution trend of pyroxene crystallized in closed system .The morphologic and compositional features reflect the magma mixing beatures of the basalt magma,and demonstrate the dynamic proeess of this mantle magma：The tholeiitic magma from the upper mantle was mixed by the magma carrying the Fe-rich pyroxene in the process moving up to the magma chamber：the mixed magma at magma chamber crystallized microlites and the rim of phenocryst；groundmass pyroxene was resulted from the quenching process of eruption. Consequently, clinopyroxenes in the Okinawa basalts keep well the records of the dynamic process of mantlemagma.