A novel organic nonlinear optical material 4-methoxy benzaldehyde-N-methyl-4-stilbazolium tosylate has been synthesized and good optical quality crystals were grown! by slow cooling solution growth technique. Powder X-ray diffraction studies have been carried out and the lattice parameters were calculated. FTIR spectra were recorded to identify the various functional groups present in the crystal. NMR spectrum studies have also been done. The powder second harmonic generation studies were done with Kurtz powder technique and the results were compared with urea. (C) 2002 Elsevier Science B.V. All rights reserved.