Gas hydrate formation is a main flow assurance concern in oil and gas production. Understanding the effects of the introduction of solid particles in the slug flow is essential to improve the efficiency and safety of multiphase production. The purpose of the present work is the experimental characterization of solid-liquid-gas slug flow with the presence of dispersed hydrate-like particles. Experimental tests were carried out with inert polyethylene particles of 0.5-mm diameter with density similar to gas hydrates (938 kg/m(3)). The test section comprised a 26-mm ID, 9-m length horizontal duct of transparent Plexiglas. High Speed Imaging and resistivity sensors was used to analyze the slug flow unit cell behavior due to the introduction of the solid particles and to measure the unit cell translational velocity, the slug flow frequency, the bubble and slug lengths, and the phase fractions. Two distinct concentrations of solid particles were tested (6 and 8 g/dm(3)). (c) 2018 American Institute of Chemical Engineers AIChE J, 64: 2864-2880, 2018