The paper aims to investigate the effects of sealed hypoxia versus natural oxygen supply, with or without summer temperature control, on the chemical components of tobacco leaves. Using tobacco lamina from Shaoguan (Guangdong) and Qujing (Yunnan) as the materials, four maintenance modes were applied: air-conditioned warehouse with sealed hypoxia, air-conditioned warehouse with natural aging, conventional warehouse with sealed hypoxia, and conventional warehouse with natural aging. The impact of storage conditions on chemical components during aging was analyzed. Compared to non-temperature-controlled conventional warehouses, temperature-controlled air-conditioned warehouses significantly slowed the rate of chemical changes in tobacco leaves, evidenced by gentler variation amplitudes in total alkaloids, polyphenols, pigments, and pH. Conventional warehouses notably accelerated pH decline and polyphenol oxidation. Under identical temperature control, sealed hypoxia more effectively retarded chemical changes than natural aging. Regional differences revealed that Qujing tobacco had higher initial polyphenol content (59.35 mg/g) and greater chemical variation than Shaoguan tobacco (29.06 mg/g), with rapid early-stage degradation stabilizing later. Temperature control is effective in delaying aging deterioration and stabilizing chemical components, particularly when combined with sealed hypoxia. For Guangdong-origin tobacco, the air-conditioned sealed hypoxia mode is recommended; for Yunnan tobacco, extended aging in temperature-controlled environments facilitates retention and conversion of aroma precursors. A differentiated storage strategy is proposed: ‘priority on temperature-controlled hypoxia for Guangdong, gradual aging dominance for Yunnan’.