Desertification is among the most pressing ecological and environmental challenges worldwide, characterized by its long-term and complex dynamics. Long records are essential to reveal its historical evolution and underlying drivers, yet satellite-based monitoring spans only the past four decades, and reconstructions from historical documents, archaeology, or sediments often lack spatial representativeness and temporal precision. Here we take the Tengger Desert as a case study and develop an integrated framework that couples shrub ring-width indices (RWI) with multi-source remote sensing indices and a desertification index (DI). Using this approach, we reconstruct desertification in the desert's peripheral zones since 1850 and investigate its drivers and cyclicity. Results show that desertification has generally weakened over the past 150 years: the northern (NTD), western (WTD), and southern (STD) margins exhibit declining trends, while the eastern margin (ETD) remains relatively stable. At the interannual scale, the reconstructed DI displays strong fluctuations, showing synchronous highs in 1972 and lows in 1978 across the four marginal zones; at the decadal scale, it reveals coherent phases, with synchronous periods in 1917-1920, 1926-1930, and 1978-1989. The dominant cycles of DI range from 2 to 10 years. NTD and WTD are controlled mainly by precipitation and drought, whereas human disturbance increasingly shapes STD and dominates ETD. Large-scale climate teleconnections modulate desertification variability, but their influence lacks consistency and persistence. Our findings provide a new framework for reconstructing long-term ecological change in arid deserts and offer scientific guidance for desertification control.