The Invalid three-wheeler is constructed on the basis of a motorbike, characterized in that has a rectangular floor /4/ to which on both sides rear parts of a motorbike /2/ and /3/ are attached, and at the front the front part of a motorbike /1/ is attached, however at the back the floor has a split flap /5/, wherein at the front of the motorbike /1/ there are two connecting elements /7/ appropriately adapted to be joined with connecting elements /6/ of the invalid wheelchair /8/.