A process for integrated production of ethanol and seaweed sap from Kappaphycus alvarezii comprising the steps of: (a) saccharification which consists of hydrolyzing washed carrageenan rich granules, obtained after extraction of sap from Kappaphycus alvarezii, using dilute sulfuric acid in the range of 0.5-5%, followed by heating the solution in the range of 80-200° C for a period in the range of 30-90 minutes to obtain reducing sugar rich hydrolysate; (b) recovering the hydrolysate as obtained in step (a) by filtration or centrifugation in the range of 5000- 7000 rpm for 15 minutes to obtain hydrolysate; (c) increasing the sugar concentration in the hydrolysate as obtained in step (b) by adding fresh Kappaphycus alvarezii granules to the filtered solution followed by repeating the step (a) and (b) till sugar concentration is attained in the range of 2 to 10%; (d) adjusting the pH of the hydrolysate as obtained in step (c) in the range of 4.5 to 8.0 using calcium hydroxide to generate insoluble salt of CaSO 4; (e) separating insoluble salts as obtained in step (d) by filtration or centrifugation in the range of 5000-7000 rpm to obtain hydrolysate; (f) desalting the hydrolysate as obtained in step (e), to remove soluble salts, by electro-dialysis; (g) enriching the hydrolysate as obtained in step (f) with nitrogen source in the range of 0.2-2.0% followed by sterilization at 121 oC for 15 minutes; (h) inoculating the yeast culture of Saccharomyces to the hydrolysate as obtained in step(g) and incubating it in the range of 25-35o C for a period in the range of 24 to 96 hours to obtain ethanol; (i) separating ethanol as obtained in step (h) from fermented broth by distillation; (j) concentrating ethanol as obtained in step (i) by distillation to obtain the desired product. (a) saccharification which consists of hydrolyzing washed carrageenan rich granules, obtained after extraction of sap from Kappaphycus alvarezii, using dilute sulfuric acid in the range of 0.5-5%, followed by heating the solution in the range of 80-200° C for a period in the range of 30-90 minutes to obtain reducing sugar rich hydrolysate; (b) recovering the hydrolysate as obtained in step (a) by filtration or centrifugation in the range of 5000- 7000 rpm for 15 minutes to obtain hydrolysate; (c) increasing the sugar concentration in the hydrolysate as obtained in step (b) by adding fresh Kappaphycus alvarezii granules to the filtered solution followed by repeating the step (a) and (b) till sugar concentration is attained in the range of 2 to 10%; (d) adjusting the pH of the hydrolysate as obtained in step (c) in the range of 4.5 to 8.0 using calcium hydroxide to generate insoluble salt of CaSO 4; (e) separating insoluble salts as obtained in step (d) by filtration or centrifugation in the range of 5000-7000 rpm to obtain hydrolysate; (f) desalting the hydrolysate as obtained in step (e), to remove soluble salts, by electro-dialysis; (g) enriching the hydrolysate as obtained in step (f) with nitrogen source in the range of 0.2-2.0% followed by sterilization at 121 oC for 15 minutes; (h) inoculating the yeast culture of Saccharomyces to the hydrolysate as obtained in step(g) and incubating it in the range of 25-35o C for a period in the range of 24 to 96 hours to obtain ethanol; (i) separating ethanol as obtained in step (h) from fermented broth by distillation; (j) concentrating ethanol as obtained in step (i) by distillation to obtain the desired product.