The main objective of the present research was investigating the effects of a floating wave barrier with square cross section installed in front of an offshore jacket structure on the wave height, base shear, and overturning moment. A jacket model with the height of 4.55 m was fabricated and tested in the 402 m-long wave flume of NIMALA marine laboratory. The jacket was tested at the water depth of 4m subjected to the random waves with a JONSWAP energy spectrum. Three input wave heights were chosen for the tests: 20 cm, 23 cm, and 28 cm. Results showed that the average decrease in the jacket’s base shear due to the presence of a floating wave barrier with square cross section was 18.97%. The use of wave barriers with square cross section also resulted in 19.78% decrease in the jacket’s overturning moment. Hence, it can be concluded that a floating wave barrier can significantly reduce the base shear and overturning moment in an offshore jacket structure.