LIFTINGS OF TENSOR FIELDS TO THE COTANGENT BUNDLE Miroslav Doupovec and Jan Kurek Key words: Natural operator, tensor field, cotangent bundle. 1991 Math. Subject Classification: 53A55, 58A20. We study geometrical constructions transforming tensor fields of type $(r,s)$ to the cotangent bundle. We present the full classification of all such natural operators in the cases $(r,s)=(0,1)$, $(r,s)=(0,2)$ and $(r,s)=(1,1)$. We also study some geometrical constructions of $(p,q)$--tensor fields on $T^*M$ by means of $(r,s)$--tensor fields on $M$, $(r,s)\ne(p,q)$.