Research on the laws of bacterial growth and rapid acquisition of the changes in concentration, structure and chemical composition of bacterial cells can provide evidence for fast bacterial detection in environmental assessment and microbiological research fields. The transmission spectra in the region of 240-900 nm of Escherichia coli suspension during growth are recorded by ultraviolet-visible spectrophotometry. The measured transmission spectra in the visible regions are interpreted based on Mie scattering theory, and the information of concentration and size of bacteria during growth are acquired. According to the ultraviolet absorption spectra of bacteria, the nucleic acid content is calculated with the absorption characteristics of chromophore amino acid and nucleic acid. The results show that the parameters interpreted from the spectra can reflect changes in concentration, size and chemical composition of bacteria during growth. These changes demonstrate that Escherichia coli cells undergo different growth stages under suitable growth condition, which is consistent with the laws of bacterial growth. Multi-wavelength transmission spectroscopy can realize bacteria motion-tracking detection during growth, and can obtain morphological characteristics and chemical composition of bacteria, which provides a new method for multiple parameters measurement of bacteria.