The demonstration of a $69.8\mathrm{nm}$ laser on $3p$ ${}^3{P}_2-3s$ ${}^1{P}_1$ ( $J=2-1$ ) transition of Ne-like Ar pumped by capillary discharge is reported in this Letter. A main current of $12\mathrm{kA}$ with rise time of $43\mathrm{ns}$ was chosen to generate the plasma in a $35\mathrm{cm}$ long capillary filling with pressure of Ar as low as $11\mathrm{Pa}$ , resulting in a gain coefficient of $0.34{\mathrm{cm}}^{-1}$ and gain–length product of 11 at $69.8\mathrm{nm}$ . Also observed is a weak laser on $3p$ ${}^3{D}_2-3s$ ${}^3{P}_1$ ( $J=2-1$ ) transition of Ne-like Ar at $72.6\mathrm{nm}$ in the same condition. In addition, multiwavelength lasing at 46.9, 69.8, and $72.6\mathrm{nm}$ was simultaneously realized in a capillary discharge plasma column, conditioning the pressure of Ar to $13\mathrm{Pa}$ .