  We calculate hyperfine structure intervals $\Delta E^{hfs}(2P_{1/2})$ and
$\Delta E^{hfs}(2P_{3/2})$ for P-states in muonic ions of lithium, beryllium
and boron. To construct the particle interaction operator in momentum space we
use the tensor method of projection operators on states with definite quantum
numbers of total atomic momentum F and total muon momentum j. We take into
account vacuum polarization, relativistic, quadruple and structure corrections
of orders $\alpha^4$, $\alpha^5$ and $\alpha^6$. The obtained numerical values
of hyperfine splittings can be used for a comparison with future experimental
data of the CREMA collaboration.
