  We present the analysis of 11 589 eclipsing binary stars identified in
twenty-one OGLE-III Galactic disk fields toward constellations of Carina,
Centaurus, and Musca. All eclipsing binaries but 402 objects are new
discoveries. The binaries have out-of-eclipse brightness between I=12.5 mag and
I=21 mag. The completeness of the catalog is estimated at a level of about 75%.
Comparison of the orbital period distribution for the OGLE-III disk binaries
with systems detected in other recent large-scale Galactic surveys shows the
maximum around 0.40 d and an almost flat distribution between 0.5 d and 2.5 d,
indepedent of population. Ten doubly eclipsing systems and one
eclipsing-ellipsoidal object were found among thousands of variables. Nine of
them are candidates for quadruple systems. We also identify ten eclipsing
subdwarf-B type binary stars and numerous eclipsing RS CVn type variables. All
objects reported in this paper are part of the OGLE-III Catalog of Variable
Stars.
