Abstract: The paper shows results obtained for event-by-event multiplicity fluctuations studied in terms of strongly intensive quantity in the Monte Carlo model of quark–gluon strings of finite pseudorapidity length. The effect of the string fusion on the fluctuation measure is presented as its dependence on the distance between the intervals of pseudorapidity in which multiplicity is determined. The results are in qualitative agreement with experimental data on Pb+Pb collisions by the ALICE experiment at the LHC.