  In this paper, we study the nonexistence of nontrivial time-periodic
solutions of the Dirac equation in Kerr-Newman-(A)dS spacetime. In the
non-extreme Kerr-Newman-dS spacetime, we prove that there is no nontrivial
$L^p$ integrable Dirac particle for arbitrary $(\lambda,p)\in
\mathbb{R}\times[2,+\infty)$. In the extreme Kerr-Newman-dS and extreme
Kerr-Newman-AdS spacetime, we show the equation relations between the energy
eigenvalue $\omega$, the horizon radius, the angular momentum, the electric
charge and the cosmological constant if there exists nontrivial $L^p$
integrable time-periodic solution of the Dirac equation, and further give the
necessary conditions for the existence of nontrivial solutions.
