A sterility test method includes: selecting strain and culture medium, preparing bacterial cultures, transcribing fingerprint characteristics in thermograms as indices to verify the characteristics, drawing the thermodynamic parameters of the thermogram, determining the positive judgment index and performing sterility test for the samples. A fully-enclosed bacteria collecting ampoule incubator includes bacteria collecting ampoule system, sample and liquid feeding system and peristalsis liquid discharge system. The sample and liquid feeding system is connected with the bacteria collecting ampoule system by the liquid intake tube; and the bacteria collecting ampoule system is connected with the peristalsis liquid discharge system by the liquid drainage tube. The invention is characterized by short inspection time, high sensitivity, high automation and accurate test results on microbial contamination. It can also provide the overall process curve on the growth conditions. Such curve is provided with relatively favorable fingerprint, which enables qualitative analysis on the microbial contamination conditions.