A method and an arrangement for controlling a burner of a suspension smelting furnace. The burner includes a reaction gas feeding device, and a fine solids feeding device. The fine solids feeding device being at an upstream end of the fine solids feeding device pivotably supported in the reaction gas feeding device. The burner including by at least one first mechanical actuator configured to center the fine solids feeding device in the annular reaction gas outlet opening. Said at least one first mechanical actuator being in response to receiving the control signal configured to perform a centering action to center the fine solids channel in the annular reaction gas outlet opening.