Single crystals of pure and thiourea doped Glycyl L-Alanine(GLA) were grown by slow evaporation method. The cell parameters were determined using single crystal X-ray diffraction method. To improve the physical properties of the GLA crystal, thiourea dopant was added by 2 mol%. EDAX studies confirm the presence of thiourea in the grown GLA crystal.The thermo gravimetric analysis (TG) and differential thermal analysis(DTA) of GLA and thiourea doped GLA(TU-GLA) crystals were performed by using TG / DTA Instrument. Dielectric constant measurements were carried out at different temperatures and frequencies. HR-SEM analysis was carried out in order to study the nature and surface features of the grown crystals.