The flow pattern becomes an important point in the study of two phases flow, for example in the steam-condensate. An experimental of two phases flow patterns of steam-condensate based on fluctuation of differential pressure in annulus horizontal pipe was conducted by varying the superficial velocity of the steam. The experimental utilised Computationan Fluid Dynamic (CFD) method with Ansys Fuent 15 as software. Geometry in this experimental is an annulus pipe with inner section was made from copper (din = 17.2 mm, d0 = 19 mm), and outer section was made from Galvenized Iron Pipe (din = 108.3 mm, d0 = 114.3 mm), and the length of annulus pipe is 1.6m. The experimental used variation of steam superficial velocity ranging from JG = 0.1409 m/s to JG=1.8620 m/s and measured in the axial position of the top, side, and bottom with a distance of 10 cm, 30 cm, 55 cm, 100 cm and 150 cm. The result show that pressure distribution pattern formed wavy. Pressure on the top and bottom decreased toward the outlet, the pressure on the side position fluctuated. The higher value of superficial velocity will make the pressure on the side position increasing