  We investigate the spectrum and wave functions of {\bar q}'q' bound states
for heavy fourth generation quarks (q') that have a very small mixing with the
three observed generations of standard model quarks. Such bound states come
with different color, spin and flavor quantum numbers. Since the fourth
generation Yukawa coupling, \lambda_{q'}, is large we include all perturbative
corrections to the potential between the heavy quark and antiquark of order
\lambda_{q'}^2N_c/16\pi^2 where N_c is the number of colors, as well as
relativistic corrections suppressed by (v/c)^2. We find that the lightest
fourth generation quark masses for which a bound state exists for color octet
states. For the the color singlet states, which always have a bound state, we
analyze the influence that the Higgs couplings have on the size and binding
energy of the bound states.
