Let (X , d, µ) be a metric measure space of homogeneous type in the sense of R. R. Coifman and G. Weiss and H 1 at (X ) be the atomic Hardy space. Via orthonormal bases of regular wavelets and spline functions recently constructed by P. Auscher and T. Hytönen, the authors prove that the product f × g of f ∈ H 1 at (X ) and g ∈ BMO(X ), viewed as a distribution, can be written into a sum of two bounded bilinear operators, respectively, from H 1 at (X ) × BMO(X ) into L 1 (X ) and from H 1 at (X ) × BMO(X ) into H log (X ), which affirmatively confirms the conjecture suggested by A. Bonami and F. Bernicot (This conjecture was presented by L. D. Ky in [J. Math. Anal. Appl. 425 (2015), 807-817]).