We report on time-resolved photometry during a 2012 January normal outburst of SU UMa .
The light curve shows hump-like modulations with a period of 0.07903 ( 11 ) d , which coincides with the known superhump period of SU UMa during superoutbursts .
We interpret this as superhump , based on the observed periodicity , profiles of the averaged light curve , and the g ^ { \prime } - I _ { c } variation during the normal outburst .
This is the first case that superhumps are detected during an isolated normal outburst of SU UMa-type dwarf novae .
The present result strongly suggests that the radius of the accretion disk already reaches the 3:1 resonance even in the midst of the supercycle .