In this paper, we claim two subjects. One is that the Weyl transform with symbol in the Gel'fand-Shilov space l r r , r ≥ 1/2 , is a trace class operator. The other one is that the Weyl transform with symbol in the generalized function (l r r )1, r ≥ 1/2 , is a continuous linear transformation from the Gel'fand-Shilov space l r r to (l r r )¹. As r > 1, Z. Lozanov- Crvenkovic and D. Peri ic have proved in [6] this result. Our second claim includes their result.