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We theoretically propose that hexagonal silicon-based crystals, $P6/m$-Si$_6$ and $P6/m$-NaSi$_6$, are topological Dirac semimetals with superconducting critical temperatures of 12 K 13 K, respectively, at ambient pressure. Band inversion occurs the Fu-Kane invariant $\mathbb{Z}_2=1$, even in absence spin-orbit coupling. The nodes protected by $C_6$ crystal rotational symmetry remain gapless Using first-principles calculations, we find pressure-induced phase transitions for $P6/m$-NaSi$_6$ external pressures 11.5 GPa 14.9 GPa, respectively. Above pressures, bands gapped $\mathbb{Z}_2=0$, while states symmetries retained.Our results may shed light into a search materials superconductivity.