We study a CP-violating triple product correlation that occurs in the decay of a neutral Higgs boson into tt̄ pairs when the Higgs boson does not have a definite CP nature. We consider the H→tt̄ decay channel as well as the gluon fusion process gg→H→tt̄. The asymmetry in Higgs decay, normalized to the H→tt̄ width, can reach the 6% percent level. In the gluon fusion process the corresponding normalized asymmetry is smaller by an order of magnitude. We present a crude estimate of this observable at the LHC.