Let R be a prime ring with extended centroid C and maximal left ring of quotients Q_ml (R). Let δ∶ R→ Q_ml (R) be a Lie derivation. Suppose that charR=2 and dim_C RC=4. It is proved that δ(x)=d(x)+ϕ(x)+W(x)+ν(x) for all x∈R, where d∶ R→Q_ml (R) is a derivation, ϕ∶ R→Q_ml (R) is a Lie derivation of a special form, W∶ R→Q_ml (R) is a weak Lie derivation of a special form, and ν∶ R→C is an additive map satisfying a specific relation.
