  We present a catalogue of variable stars in the near-infrared wavelength
detected with overlapping regions of the 2MASS public images, and discuss their
properties. The investigated region is in the direction of the Galactic center
(-30 < l < 20, |b| < 20), which covers the entire bulge. We have detected 136
variable stars, of which 6 are already-known and 118 are distributed in |b| < 5
region. Additionally, 84 variable stars have optical counterparts in DSS
images. The three diagrams (colour-magnitude, light variance and colour-colour
diagrams) indicate that most of the detected variable stars should be
largeamplitude and long-period variables such as Mira variables or OH/IR stars.
The number density distribution of the detected variable stars implies that
they trace the bar structure of the Galactic bulge.
