  Based on $(2712.4 \pm 14.3) \times 10^{6}$ $ e^{+}e^{-}\to\psi(3686)$ events
collected with the BESIII detector operating at the BEPCII collider, we report
the first evidence of $\chi_{c0}\to \Lambda\bar \Lambda \phi$ decays and the
first observation of $\chi_{c1,2}\to \Lambda\bar \Lambda \phi$ decays, with
significances of $4.5\sigma$, $11.3\sigma$ and $13.0\sigma$, respectively. The
decay branching fractions of $\chi_{c0,1,2}\to \Lambda\bar \Lambda\phi$ are
measured to be $( 2.99\pm1.24\pm0.19) \times 10^{-5}$, $(6.01\pm0.90\pm0.40
)\times 10^{-5}$, and $(7.13\pm0.81\pm0.36) \times 10^{-5}$, where the first
uncertainties are statistical and the second systematic. No obvious enhancement
near the $\Lambda \bar{\Lambda}$ production threshold or excited $\Lambda$
state is found in the $\Lambda \phi$ (or $\bar{\Lambda}\phi$) system.
