Abstract Polycaprolactone/silica microporous hybrid membranes were produced in two steps: A microporous polycaprolactone membrane with an interconnected porosity of 80% was obtained via a freeze extraction procedure, then silica was formed by a sol–gel reaction inside the micropores using tetraethyl orthosilicate, TEOS, as silica precursor. It is shown that silica forms a thin coating layer homogeneously distributed over the pore walls when sol–gel reaction is catalyzed by hydrochloric acid, while it forms submicron spherical particles when using basic catalyzer. Some physical properties and the viability and osteoblastic differentiation of bone marrow rat mesenchymal stem cells cultured on pure and hybrid membranes were studied. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3229–3236, 2014.