Abstract: This study presents the successful synthesis of plasmonic silver nanoparticles (Ag NPs) using laser-induced deposition (LID) on both rigid glass and flexible polydimethylsiloxane (PDMS) substrates. The resulting nanostructures are characterized using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis, demonstrating uniform arrays of Ag nanoparticles with high deposition density and particle sizes ranging from 40 to 90 nm. Silver nanoparticles deposited on PDMS exhibit strong adhesion and maintain structural integrity under mechanical deformations, such as bending and stretching, making them ideal for flexible sensor applications. Surface-enhanced Raman spectroscopy (SERS) measurements using Rhodamine 6G (R6G) as a model analyte reveal that silver nanostructures on PDMS produce a signal comparable to those on glass, with a detection limit of 10–8 g/L for R6G. This study highlights the potential of PDMS as a flexible substrate for SERS-active sensors in biomedical and environmental applications, providing a scalable and efficient approach for detecting analytes, including disease markers and toxic substances.