The invention relates to a method of controlling the production of filler-containing paper. Filler and retention agent are both delivered to the paper manufacturing system in such a process of paper manufacture. The amount of filler in the paper is also measured, as is also the filler concentration or the total concentration in the white water or the stock. Filler is delivered in a quantity such that the system will be buffered with filler to a generally pre-determined concentration level (control value), which is followed via measuring processes. The continual addition of retention agent is based exclusively on the amount of filler in the paper measured at that moment in time, such that when the measured amount of filler present is lower than a desired level, the addition of retention agent is increased, while when the measured amount of filler present is higher than a desired level, the addition of retention agent is reduced and the continual addition of filler is based, at least seen in the long term, exclusively on the concentration level of filler measured in the white water or the stock, and so that when the measured level is lower than the control value, the addition of filler is increased, while when the measured level is higher than the control value, the amount of filler added is decreased.