Fire history over the last 225 years has been reconstructed far the Lake Duparquet area in Northwestern Quebec. The cumulative distribution of burn areas has shown two distinct periods of stable fire cycle. The present fire cycle of -90 years contrasts with the -53 year fire cycle observed for the period before -1870. This change appears unrelated to fire suppression by man since the same trend is observed an islands of the lake where fire history is independent of the mainland fire history. This change in fire cycle is associated to a long term increase in mean ring width for a white cedar (Thuja occidentalis L.) chronology from the same area. Since the main factor affecting the indexed chronology is summer precipitation, a climatic control aver fire cycle is suggested.