Inorganic semiconductor quantum dots (QDs) have emerged as promising sensitizers for triplet-triplet annihilation photon upconversion (TTA-UC) owing to negligible internal energy loss and broad, tunable absorption bands of QDs. The overall quantum efficiency of QD-sensitized TTA-UC is usually controlled by the efficiency of triplet energy transfer (TET) across the QD/molecule interfaces. Recently, we reported a new mechanism termed proton shuttle-assisted triplet energy transfer (PS-TET) that substantially enhanced both the rate and efficiency of TET from QDs to surface-anchored dyadic molecules. Here, we investigate the effectiveness of PS-TET in TTA-UC applications. Compared to a QD-dyad system lacking the proton shuttle, the PS-TET-based system exhibits approximately three-fold enhancement in the TTA-UC quantum efficiency, exemplifying the benefit of PS-TET in spin-triplet-related photochemistry. Furthermore, substituent effects on TTA-UC performance of the QD-dyad systems reveal that triplet properties of the surface-anchored molecules also play a crucial role in determining the TTA-UC performance.