  We present in this paper the first near infrared study of the young open
cluster NGC 2244, which is well known for its partially embedded nature in the
Rosette Nebula. Based on the spatially complete 2 Micron All Sky Survey, the
young OB cluster indicates apparent substructures. It is surprisingly resolved
into a compact core that matches well the congregation of massive OB stars in
the optical, a satellite cluster at a distance of 6.6 pc in its west and
probably a major stellar aggregate resembling an arc in structure right below
the core. This infrared study provides various new updates on its nature of the
young open cluster, including its central position, physical scale and stellar
population. A disk fraction of $\sim 20.5\pm2.8%$ is achieved for its members
with masses above 0.8 $M_{\odot}$. NGC 2244 is hence a unique example for the
study of embedded clusters.
