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The Mesozoic-Cenozoic exhumation and deformation of the northeastern Qinghai–Tibetan Plateau generated extensive regional rugged mountains. We aimed to explore the prolonged kinematic evolutionary history since the Mesozoic. We collected Mesozoic magmatic rock samples from the Chaqiabeishan-Shaliuquan lithium‑beryllium ore district in the Northern Qaidam tectonic belt (NQTB) to constrain the cooling exhumation history using apatite fission track (AFT) thermochronology. Twenty samples yielded AFT ages from 111 to 11 Ma, including four age groups:111–103, 89–75, 71–47, and 30–11 Ma, with mean track lengths of 12.5–11.2 μm. Four thermal history phases of 120–90, 90–50, 50–20, and 20–0 Ma were established based on the inverse thermal model and isostatic adjustment of the lithosphere. Additionally, the average cooling rates of the four phases were 1.67 ± 0.17, 1.25 ± 0.13, 0.33, and 1.75 ± 0.5 °C/Myr, with a corresponding exhumation amount of 1.15 ± 0.07 km, 0.98 ± 0.06 km, 0.86 ± 0.05 km, and 1.09 ± 0.06 km respectively, and the maximum exhumation was 6.021–6.787 km since 120 Ma. In the first phase, the far-field effects of Mid-Tethys Ocean subduction and closure drove the rapid exhumation of the research area. The closure of the Neo-Tethys Oceans and the continuing collision of the India-Asia plate disturbed the northeastern plateau, inducing regional backlash fault events in the NQTB, demonstrated in the second phase of thermal history. The third phase of the stable tectonic setting is consistent with previous research results, suggesting a similar cooling history for the NQTB and Qilian Mountains, evidenced by the widespread absence of Eocene to Miocene cooling signals. The rapid exhumation and reactivation of the NQTB and Qilian thrust fault system since 20 Ma represents the final stage of growth and expansion of the northeastern Qinghai–Tibet Plateau. The multi-phased tectonic events and cooling uplift history of the North Qaidam Tectonic Belt (NQTB) since the Late Mesozoic are revealed by apatite fission track data from the Chaqiabeishan-Shaliuquan Li Be ore district. In addition, thermochronological ages of multi-stage tectono-thermal events are recorded extensively on the northeastern Qinghai-Tibet Plateau. The regionally extensive Early Cretaceous thermochronological signal of the NQTB and the Qilian Mountains are recorded later than the Eastern Kunlun Orogenic Belt, which implies progressive propagation of tectonic stress from plateau collision frontier to the northeastern margin in the Early Cretaceous. The Cenozoic India-Asia plate convergent collisional transmitted stresses produced significant regional tectonic deformation in northeastern Tibet, and the extensive Cenozoic thermochronological signal in northern Tibet emphasizes the similar cooling history of the NQTB and Qilian Mountains. The cooling break and weak age record from the Middle Eocene to Oligocene probably suggest the tectonic reorganization of the northeastern plateau to accommodate out-of-sequence tectonic deformation and crustal shortening. [Display omitted] • Research yielded four stage-pulse exhumation happened during Cretaceous. • Quantitatively recovered the cooling and exhumation history. • The northeastern Plateau experienced sustained deformation since the Late Cretaceous. • Rapid cooling event in the Miocene record final activity of the Chaqiabeishan fault. [ABSTRACT FROM AUTHOR]