A multiobjectiveoptimizationbased emission spectral tomography alg or ithm(EST) is proposed. Its reconstruction results for asymmetrical emission coefficient field are studied by numerical simulation with compute r. The results show that this algorithm has faster convergences and higher recon struction precision than that of traditional algorithms and is suitable for real time reconstruction of emission coefficient field with incomplete data. In the experiment of argonarc plasma diagnosis, the threedimensional reconstructio ns of temperature and atomic (ionic) density fields are accomplished with this a lgorithm and the spectrum relativeintensity method.