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The 7 January 2022 M w 6.6 Menyuan earthquake struck the Qilian-Haiyuan fault zone, NE Tibet, offering a chance for understanding the regional seismogenic structure and rupture behavior. We use Interferometric synthetic aperture radar data to study the coseismic and early postseismic deformation of the event. Coseismic modelling highlights that the earthquake activated two strike-variable high-angle strike-slip faults (one SE-trending main fault and one ENE-striking secondary fault) corresponding to only part of the Lenglongling and Tuolaishan faults. Further postseismic analysis not only reveals a localized postseismic signal of up to ∼3 cm related to the mainshock but identifies an obvious coseismic signal of up to ∼2.3 cm associated with an M W 5.1 aftershock characterized by sinistral strike-slip-faulting. The 2022 Menyuan earthquake, large aftershock and 2016 M w 5.9 thrust-faulting Menyuan earthquake illuminate a positive flower structure of the Lenglongling fault. By a joint analysis of the inversions, fault kinematics and historical earthquake, we suggest that fault branches and low pre-stress jointly restrain the maximum rupture size in the 2022 Menyuan event. • Coseismic deformation of 2022 Menyuan earthquake and its largest aftershock and postseismic deformation of mainshock are detected with InSAR. • Two strike-variable strike-slip faults with different dips are activated during the 2022 Menyuan earthquake. • Fault branches and low pre-stress may jointly limit the lateral slip propagation in the 2022 Menyuan earthquake. [ABSTRACT FROM AUTHOR]