  Heavy-flavour (HF) quarks, i.e. charm and beauty, are produced in the early
stages of ultra-relativistic collisions via hard scattering processes. The
measurement of heavy flavour as a function of charged-particle multiplicity not
only provides information on how the production mechanisms are influenced by
the event activity, but can also be considered as a tool to test the role of
multiple parton interactions. Furthermore, charged-particle multiplicity
studies are essential for reference measurements, to tune theoretical models
and to provide information on the global characteristics of events. In ALICE,
charged-particle multiplicity and heavy-flavour production in the hadronic and
electronic decay channels are measured at central rapidity while HF-decay muons
and $\rm J/\psi \rightarrow \mu^{+}\mu^{-}$ are measured at forward rapidity.
In this contribution, results will be presented on relative $\rm J/\psi$,
average D-mesons and leptons from HF hadron decay yields as a function of
charged-particle multiplicity in proton-proton (pp) collisions at $\sqrt{s}$ =
5.02, 7, 8 and 13 TeV. These results will also be compared to theoretical model
calculations.
