The Haladala gabbroic pluton at Tekex is the largest layered mafic-uhramafic intrusion in the northern margin of southwestern Tianshan orogenic belt, and contains abundant Fe-Ti oxides (up to 15% ). The rocks were highly fractionated with low Fo (64 ~75) olivine, low An plagioclase ( mostly andesine-labradorite), and low Mg^# ( 0. 66 ~ 0. 87 ) clinopyroxene ( salite or augite).Fe-Ti oxides consist mostly of V-Ti-magnetite ( TiO2 = O. 8% ~ 20. 6% ; V2 O3 = 0. 10%~ O. 83 % ) that always coexists with ilmenite or contains exsolution lamellae of ilmenite. The late-crystallizing micas on the periphery of anhedral Fe-Ti oxides are dominant phlogopites and minor hiotites, and have relatively high F and C1 contents ( "F + Cl" up to 3. 14% ), indicating a water-poor source. The Haladala gabbros show wide range of major element concentrations ( e. g. , Mg^# = O. 48 ~ 0. 73 ). The compositional variation of olivine-bearing gabbros was likely caused by fractional crystallization and/or accumulation of olivine and plagioclase, while that of olivine-free gabbros was mostly attributed to plagioclase and Fe-Ti oxides accumulation. Fe-Ti enrichment in the Haladala gabbros is the result of fractional crystallization of primary low oxygen fugacity and water-poor magma. The Haladala gabbros were derived from high degree partial melting of mantle source, which might record the early magmatism of the Tarim mantle plume expressing firstly in the pre-existing lithosphere weakness zones such as the Tianshan orogenic belt.