We consider the weighted Bergman spaces HL 2 (B d , µ λ ), where we set dµ λ (z) = c λ (1 − |z| 2 ) λ dτ (z), with τ being the hyperbolic volume measure. These spaces are nonzero if and only if λ > d. For 0 < λ ≤ d, spaces with the same formula for the reproducing kernel can be defined using a Sobolev-type norm. We define Toeplitz operators on these generalized Bergman spaces and investigate their properties. Specifically, we describe classes of symbols for which the corresponding Toeplitz operators can be defined as bounded operators or as a Hilbert-Schmidt operators on the generalized Bergman spaces.Mathematics Subject Classification (2010). Primary 47B35; Secondary 32A36, 81S10.