Connection assembly for coupling an auxiliary drive system to a wheelchair for disabled people, of the type comprising: - a fixing structure adapted to be fixed to the framework of said wheelchair; - at least one longitudinal member operatively connected to said fixing structure so that the longitudinal development axis (X 1) of said longitudinal member is substantially parallel to the advancement direction (X 2) of said wheelchair; - connection means associated with the free end of said longitudinal member and said auxiliary drive system, said connection means being configured to allow rapid coupling and decoupling of said auxiliary drive system to/from said wheelchair; characterized in that said connection means comprise: - a main body in which a first seat and a second seat are defined, each of said seats (6, 7) being defined with a substantially "C" shaped profile and being provided with an access mouth (61, 71), said main body comprising a locking mechanism operatively associated at said second seat and configured to assume with respect to said main body a first configuration according to which access to said second seat is allowed through said access mouth and a second configuration according to which said access mouth of said second seat is occluded; - a pin and a driving element both having a substantially longitudinal development, defined substantially mutually parallel and integral, said pin being configured to be received in said first seat and said driving element being configured to be inserted into said second seat and to carry out the translational motion of said locking mechanism from said first configuration to said second configuration upon insertion of said pin in said first seat and upon rotation of said drive system with respect to said wheelchair around the axis of rotation (Y 1) defined by said pin; said main body with said locking mechanism being configured to be connected to said free end of said longitudinal member and said pin and said driving element being configured to be connected to said auxiliary drive system or vice versa. - a fixing structure adapted to be fixed to the framework of said wheelchair; - at least one longitudinal member operatively connected to said fixing structure so that the longitudinal development axis (X 1) of said longitudinal member is substantially parallel to the advancement direction (X 2) of said wheelchair; - connection means associated with the free end of said longitudinal member and said auxiliary drive system, said connection means being configured to allow rapid coupling and decoupling of said auxiliary drive system to/from said wheelchair; - a main body in which a first seat and a second seat are defined, each of said seats (6, 7) being defined with a substantially "C" shaped profile and being provided with an access mouth (61, 71), said main body comprising a locking mechanism operatively associated at said second seat and configured to assume with respect to said main body a first configuration according to which access to said second seat is allowed through said access mouth and a second configuration according to which said access mouth of said second seat is occluded; - a pin and a driving element both having a substantially longitudinal development, defined substantially mutually parallel and integral, said pin being configured to be received in said first seat and said driving element being configured to be inserted into said second seat and to carry out the translational motion of said locking mechanism from said first configuration to said second configuration upon insertion of said pin in said first seat and upon rotation of said drive system with respect to said wheelchair around the axis of rotation (Y 1) defined by said pin;