Gas–solid cyclones are broadly employed in the industrial sector. Even though numerical methods are currently a strong tool for predicting the characteristics of flow patterns inside cyclone separators, they should be validated using experimental data. On the other hand, several practical aspects must be considered to analyze the operating circumstances of cyclones and their design optimization. This paper summarizes cyclone working principles and measurement techniques utilized in experimental analysis. Besides, experimental aspects, including various geometries, surface roughness, erosion rate, external electric field, particle properties, etc., are discussed. Eventually, research gaps and future directions are introduced.