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abstract: 'We present the results of near-infrared imaging and spectroscopic observations of the young, core-collapse supernova remnant (SNR) G11.2–0.3. In the 164 image, we first discover long, clumpy filaments within the radio shell of the SNR, together with some faint, knotty features in the interior of the remnant. The filaments are thick and roughly symmetric with respect to the NE-SW elongation axis of the central pulsar wind nebula. We have detected several lines and line toward the peak position of the bright southeastern filament. The derived extinction is large ($A_V=13$ mag) and it is the brightest 164 filament detected toward SNRs to date. By analyzing two 164 images obtained in 2.2 yrs apart, we detect a proper motion corresponding to an expansion rate of $0.''''035\pm 0.''''013$ yr$^{-1}$ ($830\pm 310$ ). In addition to the features, we also discover two small 212 filaments. One is bright and along the SE boundary of the radio shell, while the other is faint and just [*outside*]{} of its NE boundary. We have detected (2-1) S(3) line toward the former filament and derive an excitation temperature of 2,100 K. We suggest that the filaments are dense clumps in a presupernova circumstellar wind swept up 