  We examine the luminosity function (LF) of [OII] emission-line galaxies in
the high-resolution cosmological simulation MassiveBlack-II (MBII). From the
spectral energy distribution of each galaxy, we select a sub-sample of
star-forming galaxies at $0.06 \le z \le 3.0$ using the [OII] emission line
luminosity L([OII]). We confirm that the specific star formation rate matches
that in the GAMA survey. We show that the [OII] LF at z=1.0 from the MBII shows
a good agreement with the LFs from several surveys below L([OII])=$10^{43.0}$
erg/s while the low redshifts ($z \le 0.3$) show an excess in the prediction of
bright [OII] galaxies, but still displaying a good match with observations
below L([OII])=$10^{41.6}$ erg/s. Based on the validity in reproducing the
properties of [OII] galaxies at low redshift ($z \le 1$), we forecast the
evolution of the [OII] LF at high redshift ($z \le 3$), which can be tested by
upcoming surveys such as the HETDEX and DESI. The slopes of the LFs at bright
and faint ends range from -3 to -2 showing minima at z=2. The slope of the
bright end evolves approximately as 1/(z+1) at z=2 while the faint end evolves
as ~3/(z+1) at $0.6 \le z \le 2$. In addition, a similar analysis is applied
for the evolution of [OIII] LFs, which is to be explored in the forthcoming
survey WFIRST-AFTA. Finally, we show that the auto-correlation function of
[OII] and [OIII] emitting galaxies shows a rapid evolution from z=2 to 1.
