This research paper describes the development, optimization and in vitro characterization of chemically cross-linked pectin-polyvinyl alcohol-co-poly(2-Acrylamido-2-methylpropane sulfonic acid) semi-interpenetrating polymer network hydrogel [pectin-PVA-co-poly(AMPS) semi-IPN hydrogel] for controlled delivery of model drug tramadol HCl. Response surface methodology based on 3(2) factorial design was used for optimization and investigating the effect of independent factors: polymer-blend ratio (pectin:PVA = X (1)) and monomer (AMPS = X (2)) concentration on the dependent variables, swelling ratio (q (18th)), percent drug release (R (18th), %), time required for 80 % drug release (t (80 %), h), drug encapsulation efficiency (DEE, %) and drug loaded contents (DLC, mg/g) in pectin-PVA-co-poly(AMPS) gels prepared by free radical polymerization. The optimized semi-IPN gel (FPP-10) showed controlled in vitro drug release (R (18th)) of 56.34 % in 18 h, t (80 %) of 30 h, and DEE of 23.40 %. These semi-IPN hydrogels were also characterized through SEM, FTIR, sol-gel analysis, swelling studies and drug release characteristics. Therefore, this newly synthesized polymeric network could be a potential polymeric system for controlled drug delivery of tramadol HCl for prolonged drug release.