  In this paper, we discuss the holographic first order QCD phase transition
with gluon condensate and the generation of gravitational waves (GWs) from the
phase transition. The first order QCD phase transition is dual to the first
order Hawking-Page phase transition from holography. We study the first order
Hawking-Page phase transition from the thermal dilatonic phase to the dilatonic
black hole phase and find the phase transition temperature is proportional to
the gluon condensate. After substituting into the phenomenological value of
gluon condensate from QCD sum rules, we find $T_c=155.38\ MeV$. In further
research, we study the GWs generated from holographic cosmic first order QCD
phase transition with gluon condensate and the produced GWs might be detected
by the International Pulsar Timing Array, Square Kilometre Array and Big-Bang
Observer. Moreover, the gluon condensate suppresses the energy density of total
GWs and peak frequency.
