Abstract: Objectives: Moderate earthquakes generally produce weaker and more spatially limited elastic deformation than large earthquakes. However, when the source is shallow and the near-surface medium is strongly heterogeneous, centimeter- to decimeter-scale deformation may occur within a narrow near-field zone. Such deformation is commonly characterized by high spatial gradients, low coherence and irregular spatial patterns, and is therefore difficult to detect using conventional InSAR observations. This study focuses on the capability of high-resolution L-band InSAR to identify intense near-field deformation associated with shallow moderate earthquakes. Methods: A sensitivity analysis was developed by considering three related aspects: the phase-to-LOS displacement conversion controlled by radar wavelength, the dependence of phase uncertainty on interferometric coherence and equivalent number of looks, and the phasegradient condition required for stable phase unwrapping. On this basis, the theoretical detectability and spatial resolvability of near-field high-gradient deformation were examined. Two shallow moderate earthquake cases in South China were then analyzed, including the 2021 Bijie M 4.5 earthquake in Guizhou and the 2026 Liuzhou M 5.2 earthquake swarm in Guangxi. Sentinel-1 C-band, ALOS-2 PALSAR-2 L-band and LT-1 L-band SAR data were processed and compared in terms of wrapped phase continuity, coherence distribution, LOS displacement, profile characteristics and deformation gradients. Results: The theoretical analysis shows that short-wavelength SAR has higher phase sensitivity under high-coherence and low-gradient conditions, whereas L-band SAR has greater tolerance to high deformation gradients because a larger LOS displacement is represented by one phase cycle. The case studies show that this advantage becomes important in vegetated, mountainous and karst areas. For the Bijie earthquake, Sentinel-1 did not provide a stable coseismic deformation signal, while ALOS-2 detected a near-field deformation zone of about 3 km in length, with LOS displacement ranging from approximately -15 cm to 10 cm. For the Liuzhou earthquake swarm, Sentinel-1 showed only weak and partly decorrelated signals, while LT-1 recovered a clearer near-field deformation pattern with a maximum LOS displacement close to 20 cm. The deformation peaks, narrow transition zones and gradient concentration areas were better preserved in the high-resolution L-band results. Conclusions: Highresolution L-band InSAR is well suited to detecting intense near-field deformation caused by shallow moderate earthquakes in complex surface environments. Its advantage is not determined by wavelength alone, but by the combined effect of longer wavelength, better coherence preservation, lower fringe density and fine spatial sampling. These results indicate that high-resolution L-band SAR can provide important observations for near-field deformation identification, damage interpretation and shallow geological process analysis.