Froth flotation has been widely used for separating and concentrating valuable minerals in an ore. Froth rheology is an important parameter that affects flotation performance by affecting froth transportation. This paper reports the results of an investigation into the effect of flotation conditions on the froth rheology, in particular the influence of frother dosage and feed grade. Atwo-factor factorial experiment program was performed in a 20 L continuously operated flotation cell. It was found that, within the boundaries of this work, varying the frother dosage has no significant influence on the froth rheology, while the feed grade exhibits a positive correlation with the froth viscosity. In line with the previous study, the froth rheology has a negative correlation with the bubble size, and a positive correlation with the fraction of the bubble lamellae covered by solid particles. The froth rheology model which has been previously developed by the authors (as a function of froth properties) was also validated in the current work. (C) 2018 Elsevier B.V. All rights reserved.