Starch, an essential plant biopolymer, plays a central role in nutrition, industry, and materials science. This review explores how vibrational spectroscopy, particularly Raman and infrared (IR) techniques, has transformed our understanding of starch’s structural complexity. By harnessing their complementary strengths, we can now analyze everything from granule morphology and crystalline polymorphs (A-, B-, C-, and V-types) to processing phenomena like gelatinization, retrogradation, and chemical modification. We begin by grounding readers in the fundamentals: Raman excels at probing glucose-ring and glycosidic backbone vibrations (notably the 480 cm−1 band), while IR reveals polar functional groups and hydrogen-bond networks (e.g., the 1047/1022 cm−1 doublet). Across polymorphs, spectroscopy uncovers distinctive spectral fingerprints such as O–H band broadening in hydrous B-type starch, mixed features in C-type, and carbonyl peaks signaling V-type inclusion complexes. We then chronicle recent technological leaps: confocal Raman micro-mapping, handheld devices coupled with machine learning (e.g., single-granule amylose quantification with R2 > 0.98, <5% error), mid-IR quantum-cascade laser imaging, and multimodal approaches that fuse IR/Raman (or Raman + NIR) for enhanced structural and compositional insight. We further discuss emerging frontiers, standardized calibration protocols, deep-learning spectral interpretation, nanoscopic techniques (TERS, nano-IR), and in vivo starch monitoring, highlighting their promise and technical challenges. Finally, we envision a future of fully integrative vibrational platforms: non-destructive, in situ probes that deliver rapid, reagent-free analysis spanning molecular design to digestibility, nutrition, and industrial use. Collectively, this chapter demonstrates that vibrational spectroscopy is not just a tool, it’s a powerful lens into starch science, bridging molecular details to real-world applications.