Let F be a real quadratic field with ring of integers O and with class number 1. Let Γ be a congruence subgroup of GL2 (O)GL2() . We describe a technique to compute the action of the Hecke operators on the cohomology H3 (G; \mathbb C)H3(;C) . For F real quadratic this cohomology group contains the cuspidal cohomology corresponding to cuspidal Hilbert modular forms of parallel weight 2. Hence this technique gives a way to compute the Hecke action on these Hilbert modular forms.