Pseudomonas aeruginosa is one of the important pathogens causing clinical pneumonia. The rapid spread of antibiotic resistance threatens our fight against bacterial infections. However, the culture-based broth microdilution method (BMD) is the gold standard method for in vitro antimicrobial susceptibility tests (ASTs), which seriously affects the therapeutic effect of patients due to longer detection time. Single-cell Raman spectroscopy (SCRS) is label-free, culture-free, rapid, accurate and low-cost. Here we research the AST of Pseudomonas aeruginosa using the Clinical Antimicrobials Susceptibility Test Ramanometry (CAST-R), based on D₂O-probed Raman spectroscopy. We selected three antibiotics (Meropenem, Ceftazidime and Cefepime) and three Pseudomonas aeruginosa strains to carry out the AST. CAST-R results show 100% essential agreement and 88.9% categorical agreement with BMD methods, and it can achieve the AST results within 4h. The speed, reliability, and general applicability of CAST-R suggest its potential utility for guiding the clinical administration of antimicrobials.