Two-phase flow is part of a multi-phase flow, which is a flow that has two phases that flow simultaneously. Two-phase flow is widely used in the industrial world, such as nuclear power plants, chemical industries, steam power plants, and the petroleum industry and the working system of the blood vessels in humans. Inflow, either one phase or multi-phase, there is a flow pattern that is used to determine fluid behavior. This study was conducted to determine the effect of gas superficial velocity, the liquid superficial velocity and viscosity on the characteristics of the flow patterns, distribution of flow pattern maps and can compare maps of flow patterns with the previous studies. This research was conducted on a pipe with a diameter of 1.6 mm which was installed at an angle of 15º to the horizontal posts and The fluid used is a mixture of air-water and glycerin with a concentration of 0% (10%, 20%, and 30%). The tools used in this study are as follows: glass pipes, mixers, compressors, gas flowmeters, liquid flowmeters, water pumps, pressure vessels, reservoirs, separators, connectors, lighting, the optical correction boxes. The variation used for the gas superficial velocity JG = 0.025-66.3 m/s and for the liquid superficial velocity JL = 0.033-4,935 m/s. The liquid fluid that has been mixed is then pumped through into a pressure vessel (pressurized tank) then flowed through the water flow meter with the specified JL. The gas fluid comes from the compressor then flows through the air flow meter with the specified pattern JG. The two types of the fluid will mix in the mixer which will then flow to the test section to take a picture of the flow pattern using a camera that has been arranged to get the flow pattern. Based on the results of the study, the flow patterns that were successfully observed were: plug, bubbly, slug annular, annular, and churn. The dominant flow pattern in this study is plug and churn. The plug flow pattern was observed for the first appearance when JG= 0.025 m/s and JL= 0.033 m/s. The bubbly flow pattern began to appear on JG= 0.025 m/s and JL= 2,297 m/s. The appearance of slug annular flow for all variations of glycerin concentration starts at JG= 3 m/s and JL= 0.033 m/s. The appearance of the annular flow pattern for the 0% and 10% glycerin concentrations appeared at JG= 50 m/s and JL= 0.033 m/s, while for the concentration of 20% the appearance of the churn flow began at JG = 1,941 m/s and JL= 4,925 m/s and 30% annular flow appears at JG = 22.6 m/s and JL= 0.033 m/s. The effect of viscosity in this study is that the plug flow makes the flow pattern shorter, while the bubbly flow results in the bubbly flow pattern becoming more round. Flow pattern maps show the distribution of different flow patterns due to the increased viscosity. The results of comparing the maps of pattern of changes in viscosity flow with previous studies showed the results that are not much different, this can be seen from the shifting of the consistent flow pattern transition lines