Using a data sample of 4.48 x 10(8) psi(3686) events collected with the BESIII detector, we present a first observation of psi(3686) -> p (p) over bar phi, and we measure its branching fraction to be [6.06 +/- 0.38(stat)+/- 0.48(syst)] x 10(-6). In contrast to the earlier discovery of a threshold enhancement in the p (p) over bar -mass spectrum of the channel j/psi -> gamma p (p) over bar, denoted as X(p (p) over bar), we do not find a similar enhancement in psi(3686) -> p (p) over bar phi. An upper limit of 1.82 x 10(-7) at the 90% confidence level on the branching fraction of psi(3686) -> X(p (p) over bar)phi -> p (p) over bar phi is obtained.