Optically transparent metal semi organic single crystal of 1,4‐diazabicyclo[2.2.2]octane‐1,4‐diium tris(nitrato)‐silver (DTNS) is synthesized using slow evaporation solution technique. This single crystal is grown with dimension up to using 1,4‐diazabicyclo[2.2.2]octane (DABCO) as solute and water and methanol as solvent in the presence metal salt silver nitrate. Single crystal X‐ray diffraction (XRD) study showed a trigonal structure with space group P3c1 and the sum formula . The composition of metal Silver (Ag) in single crystal is confirmed through Energy Dispersive X‐Ray Analysis. The confirmation of various functional groups in DTNS molecular structure is characterized by Fourier Transform Infrared Spectroscopy (FT‐IR). UV–Visible absorption study showed the cut‐off wavelength at 250 nm with transparency 350–700 nm and the bandgap is about 3.3 eV. The thermal stability and melting point temperature is analyzed by Thermogravimetry‐Differential Scanning Calorimetry (TG/DSC). The third order Non Linear Optics (NLO) efficiency of the synthesized crystal is times greater than that of KDP. All of these analysis implies that DTNS crystal can be beneficial element for non‐linear optical applications.