  The recent IceCube detection of significant neutrino flux from the inner
Galactic plane has provided us valuable insights on the spectrum of cosmic rays
in our Galaxy. This flux can be produced either by a population of Galactic
point sources or by diffused emission from cosmic ray interactions with the
interstellar medium or by a mixture of both. In this work, we compute diffused
gamma-ray and neutrino fluxes produced by a population of giant molecular
clouds (GMCs) in our Galaxy, assuming different parametrizations of the
Galactic diffused cosmic ray distribution. In particular, we take into account
two main cases: (I) constant cosmic ray luminosity in our Galaxy, and (II)
space-dependent cosmic ray luminosity, based on the supernovae distribution in
our Galaxy. For Case-I, we found that the neutrino flux from GMCs is a factor
of $\sim 10$ below compared to $\pi^0$ and KRA$_\gamma$ best-fitted models of
IceCube observations at $10^5$ GeV. Instead, for Case-II the model can explain
up to $\sim 90 \%$ of the neutrino flux at that energy. Moreover, for this last
scenario IceCube detector could be able to detect neutrino events from the
Galactic centre regions. We then calculated gamma-ray and neutrino fluxes from
individual GMCs and noticed that several current and future Cherenkov
telescopes and neutrino observatories have the right sensitivities to study
these objects. In particular, very neutrino-bright region such as Aquila Rift
is favourable for detection by the IceCube-Gen2 observatory.
