Adhesive is bonding material most widely used in manufacturing sectors like shoe, wood, textile,rnpapers, and others. Most of these manufacturing sectors rely on using petroleum-basedrnadhesives such as urea formaldehyde, fevicol, polyvinyl acetate, and phenol formaldehydernresins. As these adhesives are produced from non-renewable resources and they are alsorncarcinogenic to human beings due to formaldehyde emission, it is necessary to preparernadhesives from bio-based sources. In this research bio-based adhesive was produced usingrnEuphorbia tirucalli latex as a renewable feedstock. The process of bio-adhesive productionrnincludes extraction of latex from branches of Euphorbia tirucalli using water as a solvent andrnmixing the extracted latex with silica to formulate the adhesive. 21.6 percentage yield of liquidrnlatex was obtained from the extraction section. Before the preparation of the bio-adhesive thernextracted latex was characterized in terms of total solid content, pH, viscosity, density and FTIR.rnDesign ExpertÂ® version11.1.0.1 with full factorial was applied to investigate the effect ofrnexperimental variables such as latex concentration (30, 40 and 50%), silica load (10, 20 andrn30parts per hundred rubber) and mixing time (15, 30, and 45 minutes) on the viscosity andrnbonding strength of the bio-adhesive. Significances of the experimental variables were analyzedrnby analysis of variance. Maximum lap shear strength (3.28MPa) with a corresponding viscosityrnof 567.2mPa.s was obtained when 50% latex concentration was mixed with 20phr silica for 30rnminutes and minimum lap shear strength (1.2MPa) with a corresponding viscosity of 398mPa.srnwas observed when 30% latex concentration mixed with 10phr silica for 15 minutes. Finally, thernprepared bio-adhesive was characterized in terms of bonding strength, thermal stability,rnviscosity, pH, and foam length by taking a sample from the experimental run which gavernmaximum lap shear strength. The results obtained confirmed that the prepared bio-adhesive isrncomparable with commercial synthetic adhesives and met the minimum requirements except withrnlimited thermal stability.