A blast furnace anomaly determining apparatus that detects an anomaly in a blast furnace using a plurality of sensors installed at different positions of the blast furnace, the anomaly determining apparatus comprising: an evaluation value calculating unit configured to calculate an evaluation value from a plurality of pieces of measurement data detected by the plurality of sensors; and an anomaly detecting unit configured to detect an anomaly in the blast furnace on the basis of the evaluation value calculated by the evaluation value calculating unit using an anomaly threshold and an anomaly premonitory sign threshold smaller than the anomaly threshold, wherein if the evaluation value is greater than the anomaly threshold, the anomaly detecting unit determines that there is an anomaly, and if a period during which the evaluation value is greater than the anomaly premonitory sign threshold is longer than or equal to a set period, the anomaly detecting unit determines that there is a premonitory sign of anomaly, characterized in that: the evaluation value calculating unit performs principal component analysis on the plurality of pieces of measurement data to calculate a Q statistic or a T 2 statistic, and calculates the evaluation value on the basis of the calculated Q statistic or T 2 statistic, wherein the T 2 statistic is an index indicating whether a signal is within a predetermined variation range and the Q statistic is an index orthogonal to the T 2 statistic and representing asynchronousness. an evaluation value calculating unit configured to calculate an evaluation value from a plurality of pieces of measurement data detected by the plurality of sensors; and an anomaly detecting unit configured to detect an anomaly in the blast furnace on the basis of the evaluation value calculated by the evaluation value calculating unit using an anomaly threshold and an anomaly premonitory sign threshold smaller than the anomaly threshold, wherein if the evaluation value is greater than the anomaly threshold, the anomaly detecting unit determines that there is an anomaly, and if a period during which the evaluation value is greater than the anomaly premonitory sign threshold is longer than or equal to a set period, the anomaly detecting unit determines that there is a premonitory sign of anomaly, characterized in that: the evaluation value calculating unit performs principal component analysis on the plurality of pieces of measurement data to calculate a Q statistic or a T 2 statistic, and calculates the evaluation value on the basis of the calculated Q statistic or T 2 statistic, wherein the T 2 statistic is an index indicating whether a signal is within a predetermined variation range and the Q statistic is an index orthogonal to the T 2 statistic and representing asynchronousness. the evaluation value calculating unit performs principal component analysis on the plurality of pieces of measurement data to calculate a Q statistic or a T 2 statistic, and calculates the evaluation value on the basis of the calculated Q statistic or T 2 statistic, wherein the T 2 statistic is an index indicating whether a signal is within a predetermined variation range and the Q statistic is an index orthogonal to the T 2 statistic and representing asynchronousness.