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We report on \chandra observations of the central region of M31. By combiningeight \chandra ACIS-I observations taken between 1999 and 2001, we haveidentified 204 X-ray sources within the central $\sim 17'\times17'$ region ofM31, with a detection limit of $\sim 2\times10^{35}$\lum. Of these 204 sources,22 are identified with globular clusters, 2 with supernova remnants, 9 withplanetary nebula, and 9 as supersoft sources. By comparing individual images,about 50% of the sources are variable on time scales of months. We also found13 transients, with light curves showing a variety of shapes. We also extractedthe energy spectra of the 20 brightest sources; they can be well fit by asingle power-law with a mean photon index of 1.8. The spectral shapes of 12sources are shown to be variable, suggesting that they went through statechanges. The luminosity function of all the point sources is consistent withprevious observations (a broken power-law with a luminosity break at$1.7\times10^{37}$\lum). However, when the X-ray sources in different regionsare considered separately, different luminosity functions are obtained. Thisindicates that the star-formation history might be different in differentregions.Comment: 42 pages, 9 figures, ApJ, accepted, Higher-resolution figures  available on reques

X‐Ray Point Sources in the Central Region of M31 as Seen byChandra