[en] The Ultra-relativistic heavy-ion collisions provide a unique opportunity to study the properties of extremely hot and dense system. At large enough temperature and/or baryon density, statistical lattice QCD (quantum chromodynamics) predicts a phase transition from hadronic matter to a new state of matter: a deconfined quarks and gluons plasma. Among the proposed signatures of the plasma, the enhancement of strangeness production is studied in the NA50 experiment. A strong enhancement of strange particle production, as compared to the yield expected from hadronic gas, has been predicted if QGP (quark-gluon plasma) formed. In NA50 experiment Pb-Pb collisions at 158 GeV/c per nucleon incident momentum at CERN/SPS, φ meson production is measured through dimuon channels and compare it to the ω meson yields. In this thesis φ meson study is based on the data collected in 2000 runs. Compared to previous measurements from 1996 and 1998, this one benefits from improvements in the experimental setup, in particular concerning the measurement of minimum bias spectrum used to determine J/ ψ, φ, ω and ρ multiplicities. The results of φ/ω ratios are presented, as a function of transverse mass and transverse energy. The present study confirms that φ/ω ratio does not depend on M_T, but increases with the collision centrality, by a factor about 2. The effective temperature analysis shows that T_φ ∼ T_ω at the order of 220 MeV. The multiplicity of ω per participant nucleon does not exhibit any N_part dependence, while φ multiplicity per participant nucleon increases with N_part. Finally, the comparison of the φ central multiplicity in Pb-Pb system between NA50 and NA49 is made with updated BR_μμ constant, also the comparison of the cross section measurement between Pb-Pb system and lighter systems is done. The evolution of production in J/ψ mass dominated region for the most central collisions is also considered by comparing to the minimum bias spectrum. (author)