Galactomannan gum was extracted from fenugreek seeds through seed grinding and sifting, washing and filtering and precipitating by ethyl alcohol and drying. Thus obtained products were submitted to innovative oxidation using microwave irradiation and sodium perborate (SPB) oxidant under a variety of conditions. Variable studied include concentration of SPB and duration of oxidation as well as pH and temperature of the oxidation reaction. Thus oxidized gum samples were subjected to chemical and chemical-microscopically analysis for quantitative determination of carboxyl and carbonyl groups and rheological properties along wilts residual SPB. Microstructural changes in the innovatively oxidized gum vis-à-vis those of conventionally oxidized gum were presented. Results indicate that the innovative oxidation using the microwave for heating the oxidation medium containing SPB consumes less time and energy than the conventional oxidation by SPB using conventional heating. Results indicate further that current oxidation using the microwave or conventional heating brings into focus oxidized galactomannan gums, which induce excellent overall color fastness when applied as thickeners in printing pastes of reactive dyes. These gums may be considered as a real substitute for sodium alginate thickener which is universally accepted thickeners for reactive printing on cotton. In addition, oxidized galactomannan gum creates eco- friendly environment during its preparation.