This paper considers the following three Roman domination graph invariants on
Kneser graphs:
Roman domination, total Roman domination, and signed Roman domination.
For Kneser graph $K_{n,k}$, we present exact values for Roman domination
number $\gamma_{R}(K_{n,k})$ and total Roman domination number
$\gamma_{tR}(K_{n,k})$ proving that for $n\geqslant k(k+1)$,
$\gamma_{R}(K_{n,k}) =\gamma_{tR}(K_{n,k}) = 2(k+1)$. For signed Roman
domination number $\gamma_{sR}(K_{n,k})$, the new lower and upper bounds for
$K_{n,2}$ are provided: we prove that for $n\geqslant 12$, the lower bound is
equal to 2, while the upper bound depends on the parity of $n$ and is equal to
3 if $n$ is odd, and equal to $5$ if $n$ is even. For graphs of smaller
dimensions, exact values are found by applying exact methods from literature.