Environmental Variability Selection (EVS) is hypothesized for the emergence of early Homo (H.) sapiens with small lithic tools in Africa. Yet, it is unclear how the EVS works when a special hominin group with advanced small lithic tools evolved from the Asian H. erectus with expedient core and flake industry. Lantian loessland in southern Chinese Loess Plateau in North China preserves continuous and concentrated hominin fossil, faunal, pollen, stone tool, paleoclimate, and landform records for last 2 million years (Ma) and is an ideal place to test this hypothesis. We reanalyzed δ13C values of soil organic and inorganic carbon from 2 Lantian loess-paleosol records to partition seasonal climate and habitat changes with synthesized lithic, faunal, and pollen data to seek cluses. We found that Lantian Gongwangling and Chenjiawo H. erectus adapts to woodland-forest habitats, manufacturing Mode 1 stone artifacts foraging subtropical animals in warm and Paleoarctic animals in cool seasons on the low and medium-high rolling loessland, while more advanced Dali hominins adapt to certain steppe-shrubland habitats manufacturing diverse small-sized lithic tools to forage more open-habitat animals in all seasons on hilly landforms. We propose that co-evolution of seasonal habitat variability and changing local landforms in 2.0–0.2 Ma advances Dali hominin's cognitive capacity for strategically using landform morphology for subsistence and manufacture small stone tools for intercepting high fluxes of seasonal resources on highly variable loessland. Seasonal landscape variability and landform evolution is the key in the EVS for the evolution from Asian H. erectus to a more advanced hominin group or species.