The thin-skinned structure in the crust of the northern Tianshan piedmont is explored by an 86-km-long, NS-trending deep seismic reflection profile through the r黰qi depression of the north margin of the Tianshan mountains. On the CDP stacking section, the first- and second-row parallel to anticlines in the north margin of the Tianshan moun-tains are shown on the segment to the south of the Shihezi. The detachments, corresponding to the reflection events at TWT 2.5~3.0 s and 5.5~6.0 s respectively, join the crustal deep structure to the reverse fault-fold zone. The Ma-nas thrust extends downwards in listric shape, merges into the detachment at about TWT 2.5 s and joins to the Qingshuihe thrust. The reflection events on 5.5~6.0 s are corresponding to the main detachment, which joins the lower Manas anticline, and finally converge to the Junggar Southern Marginal Fault. A 12~14 km-thick sedimentary basin exists on the region in the north to the Shihezi. The depth of the Moho discontinuity beneath the Junggar basin is about 45 km, and increases southwards to 50 km. The crustal structure inferred from the deep seismic sounding profile and the Bouguer anomaly in the same region is consistent with the image from the deep seismic reflection profile. The seismogenic model of the 1906 Manas earthquake is related to the fault system, which consists of the Qingshuihe thrust, the detachments and the shallow Manas ramp. The thin-skinned structure in the crust of the northern Tianshan piedmont is explored by an 86-km-long, NS-trending deep seismic reflection profile through the r 黰 qi depression of the north margin of the Tianshan mountains. On the CDP stacking section , the first- and second-row parallel to anticlines in the north margin of the Tianshan moun-tains are shown on the segment to the south of the Shihezi. The detachments, corresponding to the reflection events at TWT 2.5-3.0 s and 5.5 ~ 6.0 s respectively, join the crustal deep structure to the reverse fault-fold zone. The Ma-nas thrust extends downwards in listric shape, merges into the detachment at about TWT 2.5 s and joins to the Qingshuihe thrust. The reflection events on 5.5 ~ 6.0 s are corresponding to the main detachment, which joins the lower Manas anticline, and finally converge to the Junggar Southern Marginal fault. A 12-14 km-thick sedimentary basin exists on the region in the north to the Shihezi. The depth of the Moho discontinui ty beneath the Junggar basin is about 45 km, and increasing southwards to 50 km. The crustal structure inferred from the deep seismic sounding profile and the Bouguer anomaly in the same region is consistent with the image from the deep seismic reflection profile. The seismogenic model of the 1906 Manas earthquake is related to the fault system, which consists of the Qingshuihe thrust, the detachments and the shallow Manas ramp.