Static and variable magnetic field radiation, using magnets and radiofrequency sources, is believed to be a stress factor in living biological systems. Here we investigated the effects of the magnetic field by static fields and radiofrequency fields on bioluminescence using as a model organism the bioluminescent bacterium Vibrio jasicida belonging to the Harvey clade. This bacterium was cultured either in the absence or in the presence of static (Bo, 0 Hz), very high frequency (VHF, 100 MHz), and ultra high frequency (UHF, 900 MHz) field irradiation in a climate chamber at three different temperatures of 20, 25 and 30 C. Deconvolution analysis of spectral emission data demonstrated the presence of two major emission peaks centered, respectively, at about 486 nm (peak# 1) and 457 nm (peak# 2) during the logarithmic phase of growth. The exposure to magnetic fields led to evident changes in the bioluminescence pattern (peak intensity and wavelength) as a function of the incubation time demonstrating measurable effects of the magnetic field in a biological system, whose significance will be discussed.