Objective: The investigation aimed to synthesize amino derivatives of various natural gums like Xanthan gum and Tamarind gum for using them as a release modulating polymer in the formulation of the hydrophilic matrix system of losartan potassium and to find the best amongst them. Developing oral sustained release matrix tablets for a drug with a constant release rate has always been a challenge to the pharmaceutical technologist. 
 Materials and Methods: Release modulating hydrophilic matrix tablets of losartan potassium were prepared by wet granulation method. A total number of 6 formulations of release modulating hydrophilic matrix tablets of losartan potassium were prepared using different polymeric ratios of Carbopol 934, aminated Tamarind gum and aminated Xanthan gum based on preliminary trial bathes. The formulated tablets were evaluated for both pre-compression and post-compression evaluation studies. 
 Results: Based on in vitro drug release study the effective formulations AXG 3 are shows a maximum similar release profile to other remains formulations with a theoretical drug release profile of losartan potassium for sustained release. Finally optimized formulation AXG 3 containing carbopol 934 (60 mg), aminated xanthan gum (40 mg), MCC (190 mg) and magnesium stearate (10 mg) showed 100±0.024 % drug release in 12 hr which is acceptable with theoretical drug release of losartan potassium for sustain release dose. Conclusion: Aminated derivatives of xanthan gum and Tamarind gum extend the drug release for 12 hr. Based on in vitro drug release studies of formulations, we concluded that the alteration in the concentration of carbopol 934 with an aminated derivative of xanthan gum in sustain release formulation development was more effective and economical.