An apparatus for preparation of bone cements (1), comprising: a mixer device (2) having: a housing body (3) defining a chamber (4), housing or able to house a predetermined quantity of a solid component (5), for example in a granular or powder form, at least an inlet port (6) for enabling access of at least a fluid towards the chamber (4) the apparatus (1) further comprising a check and closing valve (7) operating in proximity of or at the inlet port (6) and being predisposed to selectively open and close the fluid passage towards the chamber (4) of the housing body (3).
