  In this paper, we study the cosmological inflation phenomenon in symmergent
gravity theory. Symmergent gravity is a novel framework which merges gravity
and the standard model (SM) so that the gravity emerges from the matter loops
and restores the broken gauge symmetries along the way. Symmergent gravity is
capable of inducing the gravitational constant $G$ and the quadratic curvature
coefficient $c_O$ from the loop corrections of the matter sector in a flat
space-time. In the event that all the matter fields, including the beyond the
standard model (BSM) sector, are mass degenerate, the vacuum energy can be
expressed in terms of $G$ and $c_O$. The parameter which measures the deviation
from the mass degeneracy is dubbed $\hat{\alpha}$. The parameters, $c_O$ and
$\hat{\alpha}$, of symmergent gravity convey the information about the fermion
and boson balance in the matter (SM+BSM) sector in number and in mass,
respectively. In our analysis, we have investigated the space of the symmergent
parameters $c_O$ and $\hat{\alpha}$ wherein they produce results that comply
with the inflationary observables $n_s$, $r$, and $\mathrm{d}n_s/\mathrm{d}\ln
k$.
  We have shown that the vacuum energy together with the quadratic curvature
term arising in the symmergent gravity prescription are capable of inflating
the universe provided that the quadratic curvature coefficient $c_O$ is
negative (which corresponds to fermion dominance in number in the matter
sector) and the deviation from the mass degeneracy in the matter sector is
minute for both boson mass dominance and fermion mass dominance cases.
