Abstract: As a key approach to controlled nuclear fusion, laser-driven inertial confinement fusion (ICF) has demonstrated scientific and engineering feasibility through achieving target energy gain greater than one. On the path toward higher gain and future fusion energy applications, hydrodynamic instabilities during implosion remain a central physics challenge, with research breadth and depth continually expanding. Among these, target bulk perturbations—such as isolated defects, density nonuniformities, and inhomogeneous dopant distributions within the ablator—have become a research frontier. This Review summarizes major progress in China (mainly at IAPCM) over the past five years in three areas: defect evolution mechanisms, dynamically stabilized implosions using laser pulses, and weakly-nonlinear growth of hydrodynamic instabilities. In defect physics, studies reveal that baroclinic vorticity deposition during shock-defect interaction is the fundamental seeding mechanism. Distinct evolution pathways for light-bubble and heavy-bubble defects, as well as their coupling with the ablation front, are clarified. Nonlinear amplification from multiple defects and significant fuel-ablator mixing enhancement due to three-dimensional vortex stretching are identified. The risk levels associated with defect locations in high-density carbon ablators are quantified, and it is shown that high-density tungsten-doped defects can induce interfacial jets by altering shock reflection configurations. An active control approach using an external transverse magnetic field to cancel fluid baroclinic vorticity via the magnetic baroclinic term is proposed. On dynamic stabilization, introducing a temporally modulated laser pulse during the main or pre-pulse generates an oscillatory acceleration field at the ablation front. By modifying the phase relation between density and pressure gradients, this field interrupts the sustained positive feedback accumulation of baroclinic vorticity, thereby suppressing perturbation growth induced by defects, surface roughness, and laser Imprints. The two effects of “dynamic stabilization” and “parametric excitation” caused by modulation parameters are revealed, along with optimization principles. In analytical theory, a weakly-nonlinear third-order model for combined hydrodynamic instabilities in planar geometry is developed, showing that shear flow enhances the nonlinear effects of the Rayleigh-Taylor instability (RTI). A two-mode RTI model predicting the nonlinear saturation amplitude is further established, demonstrating the key role of mode coupling in determining the root-mean-square saturation amplitude. These achievements advance the understanding of ICF implosion hydrodynamic instabilities from three perspectives: mechanism understanding, active control, and theoretical modeling. China has established a comprehensive research capability integrating physics understanding, theoretical modeling, numerical simulation, and experimental validation, providing a robust physical foundation for high-gain target design and performance optimization toward future fusion energy.