We report a search for the charmless hadronic decay $B^0toeta pi^0$ with a data sample corresponding to an integrated luminosity of 694 $rm fb^{-1}$ containing $753times10^6$ $Bbar{B}$ pairs. The data were collected by the Belle experiment running on the $Upsilon(4S)$ resonance at the KEKB $e^+e^-$ collider. We measure a branching fraction $mathcal{B}(B^0toetapi^0)=(4.1^{+1.7+0.5}_{-1.5-0.7})times 10^{-7}$, where the first uncertainty is statistical and the second is systematic. Our measurement gives an upper limit of $mathcal{B}(B^0toetapi^0)<6.5times 10^{-7}$ at 90% confidence level. The signal has a significance of $3.0$ standard deviations and constitutes the first evidence for this decay mode.
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