A study was conducted to evaluate the effect of fiber content and incorporation of natural resin on the water absorption behavior and swelling in thickness of sugarcane bagasse (SB)-reinforced epoxy-natural resin fiber-boards. Artificial (epoxy) and natural resins (cashew nut shell liquid (CNSL) resins, black dammar and pine resins) were used as a binder. The weight proportions of fiber: epoxy + hardener: natural resin were viz., 1:1:1.50, 1:1:1.75, 1:1:2. The lowest water absorption percent value for the sample immersed for 2 h and 24 h is shown by board prepared by mixing cashew nut shell liquid resin. There was less swelling in the thickness of the fiber board made with the fiber to resin weight ratio of 1:2.75. The cashew nut shell liquid resin was found to be effective in terms of Water absorption (WA) and thickness swelling (TS). Hence, the cashew nut shell liquid resin would be an alternate source for artificial resin source with less environmental hazards.