The present invention relates to a valve cusp sizer (100) for determining the size of a valve cusp corresponding to the size of a heart valve. The valve cusp sizer (100) comprises a circular arc shaped front surface (10) to come in contact with biological tissue a back surface (20) located on the surface opposite the front surface (10) and a nub (30) protruding from the back surface (20). By eliminating a handle and an attachment part for said handle from prior valve cusp sizers and instead forming a nub (30) capable of being grasped by forceps tweezers etc. it is possible to reduce the size of the valve cusp sizer while retaining necessary functions.
