Differentiation of integrals of functions from the class Lip(1,1)(I2) with respect to the basis of convex sets is established. An estimate of the rate of differentiation is given. It is also shown that there exist functions in Lip(1,1)(IN), N ≥ 3, and H1ω(I2) with ω(δ)/δ → ∞ as δ → +0 whose integrals are not differentiated with respect to the bases of convex sets in the corresponding dimension