Abstract: A limited-DTW method which makes dynamic match by tracking the points in the trajectory between batches was proposed to solve the inherent unequal length problem in the batch process. Meanwhile the serious shortcomings of traditional method in data wasting and the distorted auto-and-cross-correlation of original process variables were overcome. The global path constraint and the distortion threshold constraint were introduced to improve the dynamic time warping. The serious lag was overcome by the limited-DTW method and it was applied in practical production by reducing the calculation. Multiway principal component analysis was used to model for the processed data by limited-DTW in the passage. The method was applied to fed-batch penicillin fermentation process. Experiments show that this method can effectively warp unequal batch to equal length and reduce the leaking alarms and nuisance alarms, which also proves that the proposed method has more reliable monitoring performance than that of the traditional method.