  We report the simultaneous extreme ultraviolet observation of magnetic
reconnection inflow and outflow in a flare on 2010 August 18 observed by the
Atmospheric Imaging Assembly on board the {\it Solar Dynamics Observatory}. We
found that during the rise phase of the flare, some plasma blobs appeared in
the sheet structure above the hot loops. The plasma blobs were ejected
bidirectionally along the sheet structure (outflow), at the same time as the
threads visible in extreme ultraviolet images moved toward the sheet structure
(inflow). The upward and downward ejection velocities are 220-460 km s$^{-1}$
and 250-280 km s$^{-1}$, respectively. The inflow speed changed from 90 km
s$^{-1}$ to 12 km s$^{-1}$ in 5 minutes. By using these velocities, we
estimated the nondimensional reconnection rate, which we found to vary during
this period from 0.20 to 0.055. We also found that the plasma blobs in the
sheet structure collided or merged with each other before they were ejected
from the sheet structure. We hypothesize that the sheet structure is the
current sheet and that these plasma blobs are plasmoids or magnetic islands,
which could be important for understanding the dynamics of the reconnection
region.
