We report on the first deep optical observations of two $gamma$-ray pulsars, both among the very first discovered by the {em Fermi} Gamma-ray Space Telescope. The two pulsars are the radio-loud PSR, J1907+0602 in the TeV pulsar wind nebula (PWN) MGRO, J1908+06 and the radio-quiet PSR, J1809$-$2332 in the Taz radio/X-ray PWN. These pulsars are relatively young and energetic and have been both detected in the X-rays by xmm, which makes them viable targets for optical observations. We observed the pulsar fields in the B and V bands with the Very Large Telescope (VLT) in June/July 2015 to search for their optical counterparts. Neither of the two pulsars has been detected down to $3sigma$ limiting magnitudes of $m_{rm v} sim 26.9$ and $m_{rm v} sim 27.6$ for PSR, J1907+0602 and PSR, J1809$-$2332, respectively. We discuss these results in the framework of the multi-wavelength emission properties of pulsars.
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