<p>Understanding the interaction between cavitation bubbles and a soft elastic boundary is of great practical significance in control and use of lasers and ultrasound in medical diagnosis and treatment. Experiments on laser-induced sub-millimeter (maximum radius of 390±10 µm) cavitation bubbles near soft elastic boundaries (prepared by agarose hydrogels with three concentrations, elastic modulus <i>E</i> = 11.7 kPa −130.9 kPa are carried out via high-speed photography. The influences of elastic modulus <i>E</i> and dimensionless standoff distance <i>γ</i> on the evolution, jet behavior, migration, and aspect ratio of cavitation bubbles are analyzed, together with the deformation and damage of the elastic boundary. Based on the jet behavior and boundary response, the interactions between cavitation bubbles and elastic boundaries are classified into six distinct regimes. Among these six regimes, two new dynamic characteristics are observed, including a novel boundary damage pattern caused by the explosive expansion of high-pressure gas within the boundary and a jet generated by the annular squeezing of the elastic boundary. Both the jet velocity and its penetration depth into the elastic boundary vary non-monotonically with <i>γ</i>, and each attains a maximum. For all three elastic boundaries, the corresponding <i>γ</i> values fall within the range 0.5–0.6.</p>