Physical conditions inside a supernova remnant can vary significantly between different positions. However, typical observational data of supernova remnants are integrated data or contemplate specific portions of the remnant. We study the spatial variation in the physical properties of the N49 supernova remnant based on a spectroscopic mapping of the whole nebula. Long-slit spectra were obtained with the slit (~4'x1.03") aligned along the east-west direction from 29 different positions spaced by 2" in declination. A total of 3248 1D spectra were extracted from sections of 2" of the 2D spectra. More than 60 emission lines in the range 3550{AA} to 8920{AA} were measured in these spectra. Maps of the fluxes and of intensity ratios of these emission lines were built with a spatial resolution of 2"x2".