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We report on the results of the Chandra observation on the central region ofthe Monoceros R2 cloud (Mon R2), a high-mass star-forming region (SFR). With adeep exposure of 100 ks, we detected 368 X-ray sources, 80% of which wereidentified with the NIR counterparts. We systematically analyzed the spectraand time variability of most of the X-ray emitting sources and provided acomprehensive X-ray source catalog for the first time. Using the J-, H-, andK-band magnitudes of the NIR counterparts, we estimated the evolutionary phase(classical T Tauri stars and weak-lined T Tauri stars) and the mass of theX-ray emitting sources, and analyzed the X-ray properties as a function of theage and mass. We found a marginal hint that classical T Tauri stars have aslightly higher temperature (2.4 keV) than that of weak-lined T Tauri stars(2.0 keV). A significant fraction of the high- and intermediate-mass sourceshave a time variability and high plasma temperatures (2.7 keV). We performedthe same analysis for other SFRs, the Orion Nebula Cluster and Orion MolecularCloud-2/3, and obtained similar results to Mon R2. This supports the earlierresults of this observation obtained by Kohno et al. (2002, ApJ, 567, 423) andPreibisch et al. (2002, A&A, 392, 945) that high- and intermediate- mass youngstellar objects emit X-rays via magnetic activity. We also found a significantdifference in the spatial distribution between X-ray and NIR sources.Comment: 21 pages, 7 figures, accepted for publication in PASJ, the complete  version with figures and tables is available at  ftp://ftp-cr.scphys.kyoto-u.ac.jp/pub/crmember/nakajima/MonR2.ps.g

X-Ray Observation on the Monoceros R2 Star-Forming Region with the Chandra ACIS-I Array