Synaptic plasticity is well known as the subcellular events involved in learning and memory. Long-term potentiation (LTP), one of the synaptic plasticity, shows synaptic specificity that is the phenomenon which LTP occurs at only the synapse where the LTP inducing stimulation comes. Furthermore, the maintenance of LTP requires de novo protein synthesis at soma. How do the newly formed proteins transfer to specific synapses from soma during LTP? Synaptic tagging and subsequent capture of synthesized proteins into the specific synapses that exposed LTP induced stimulation is one of strong hypothesis which explains synaptic specificity. A lot of effort to discover the synaptic tag has been done in postsynapse, however, synaptic tag molecules in presynapse is not yet explored. In the present study, we tried to investigate presynaptic tag molecules at mouse hippocampal DG-CA3 synapse where is known to be the site of presynaptic LTP. We first prepared mouse hippocampal slice and induce LTP by using forskolin, then cut out stratum lucidum (SL) that is DG-CA3 synapse region. SL was homogenate and fractionationed to get synaptsomal fraction (P2'). This synaptosomal fraction was analyzed by mass spectrometry and compared to control. We will show the presynaptic tag candidate molecules from the mass data and the experiments that verify the proteins as the presynaptic tag.