The P-wave velocity disturbance images beneath centraleastern Gangdese were obtained through teleseismic P-wave traveltime tomographic inversion for the data collected from 197 portable broadband seismic stations. Our resultant images reveal a complicated seismic spatial pattern of the velocity structure occurring in the crust and upper mantle in the study region. Firstly, a strong low-velocity anomaly belt occurs beneath the Tethyan Himalaya north of the South Tibet Detachment (STD). But the north of the strong lowvelocity anomaly, far from the rifting zone, shows no obvious evidence to go through the Yarlung Zangbo Suture (YZS). This conclusion is quite different from those by previous geologists. Lowvelocity anomaly occurs beneath the YadongGulu (YGR) and the ComeiSangri (CSR) rift systems, but intensities of the anomaly are lower than that beneath Tethyan Himalaya. Instead, strong high velocity anomaly was observed in the centralsouthern Lhasa Terrane bounded between the YGR and the CSR. The results show that the Crustal Channel Flow affecting the structural evolution of the crust in the QinghaiTibet Plateau is mainly distributed beneath the Tethyan Himalaya region, as well as in the Gangdese region to the north of the YZS, likely along the rifting belt. Secondly, the highvelocity anomaly of the upper mantle to west of the study area, interpreted as a manifest of the Indian lithospheric mantle, extends about 100 km or more to the north of the YZS, while the anomaly to east of the study area does not go through the YZS but stagnates under High Himalaya, ~100 km south of the YZS. This is consistent with some previous results which show a systematic westtoeast change of the subduction angle of Indian lithospheric mantle near the study region. In addition, the tomographic result suggests that deepseated lowvelocity anomalies to southeast of Gangdese root into the base of upper mantle. This phenomenon may be related to the westward retreat of the eastward subducted Burmese arc during the clockwise rotation of the Sunda block.