Abstract In addressing the broad spectrum of applications for optical pressure sensors, their predominant drawback lies in their limited sensitivity to pressure fluctuations. To overcome these constraints, this study introduces a luminescent manometer harnessing the emission properties of Cr 3+ ions in Li 3 Sc 2 (PO 4 ) 3 , operational in three distinct reading modes: spectral shift, ratiometric, and lifetime‐based. Notably, the conducted research establishes this luminescent manometer as the most sensitive reported to date in both spectra shift (λ/dp = 23.9 nm/GPa) and lifetime‐based (S R = 93.56%/GPa) modes. A departure from conventional lifetime‐based luminescent pressure gauges, Li 3 Sc 2 (PO 4 ) 3 :Cr 3+ exhibits a prolongation of lifetime of the 4 T 2 state correlated with increasing pressure. The advantages extend beyond sensitivity, encompassing a three‐fold surge in emission intensity with pressure escalation from ambient to 3 GPa, coupled with minimal susceptibility to temperature‐induced fluctuations. Unquestionably, Li 3 Sc 2 (PO 4 ) 3 :Cr 3+ showcases remarkable manometric performance, validating its significant application potential in diverse scenarios within the realm of optical pressure sensors.