  We present the final results obtained by the MACRO experiment in the search
for GUT magnetic monopoles in the penetrating cosmic radiation, for the range
$4\times 10^{-5}< \beta < 1$. Several searches with all the MACRO sub-detectors
(i.e. scintillation counters, limited streamer tubes and nuclear track
detectors) were performed, both in stand alone and combined ways. No candidates
were detected and a 90% Confidence Level (C.L.) upper limit to the local
magnetic monopole flux was set at the level of $1.4\times 10^{-16}$ cm$^{-2}$
s$^{-1}$ sr$^{-1}$. This result is the first experimental limit obtained in
direct searches which is well below the Parker bound in the whole $\beta$ range
in which GUT magnetic monopoles are expected.
