Implementations of the present specification provide abnormal sample prediction methods and apparatuses. The method includes: obtaining a sample to be tested, wherein the sample to be tested comprises feature data with a given dimension, and wherein the given dimension is a first quantity; performing dimension reduction processing on the sample to be tested by using multiple dimension reduction methods to obtain multiple processed samples; inputting the multiple processed samples to multiple corresponding processing models to obtain scores of the multiple processed samples, wherein an ith processing model Mi in the multiple processing models scores the corresponding processed sample Si based on a hypersphere Qi; determining a comprehensive score of the sample to be tested based on scores of the multiple processed samples; and classifying, based on the comprehensive score, the sample to be tested as an abnormal sample.