Plant aging and senescence are key determinants of lifespan, yet the coordinated changes in endogenous polyamines and hormones during long-lived tree aging remain largely unclear. Cinnamomum camphora exhibits sequential senescence from leaves to trunk, with leaf physiology shifting toward senescence around 450 years. This study aimed to clarify the patterns of polyamines and hormones across a wide age gradient (10–810 years) and their associations with aging in ancient C. camphora. Newly expanded leaves were analyzed using curve fitting, correlation, regression, and path analysis. Tree age significantly influenced most polyamine and hormone indices, except for indole-3-acetic acid (IAA), abscisic acid (ABA), and salicylate glucoside (SAG). Spermidine (Spd) and gibberellic acid (GA) were negatively correlated with aging, and cytokinin (CK) and cadaverine (Cad) were positively correlated with aging. Free salicylic acid (SAF) was closely related to the senescence transition point. Polyamines and hormones interacted strongly. Cad was positively correlated with CK, and Spd was positively correlated with GA. A model combining Spd, GA/ABA, and CK/GA reliably predicted ancient tree age. Overall, Spd and CK exhibited the strongest negative and positive correlations with aging, respectively, providing insights into the physiological regulation of longevity in ancient trees.