In the best observed Pleiades cluster, the luminosity function(LF) and mass function(MF) for main sequence(MS) stars extended to $Mv{approx}15.5(V{approx}21)$ are very similar to the initial luminosity function(ILF) and initial mass function(IMF) for field stars in the solar neighborhood showing a bump at log $m{simeq}-0.05$ and a dip at log $m{simeq}-0.12$. This dip is equivalent to the Wielen dip appearing in the LF for the field stars. The occurence of these bump and dip is independent of adopted mass-luminosity relation(MLR) . and their characteristics could be explained by a time-dependent bimodal IMF. The model with this IMF gives a total cluster mass of $~700M_igodot,;~25$ brown dwarfs and $~3$ white dwarfs if the upper mass limit of progenitor of white dwarf is greater than $4.5M_igodot$. The cluster age on the basis of LF for brightest stars is given by $~8 imes10^7yr$ and all stars in the cluster lie along the single age sequence in the C-M diagram without showing a large dispersion from the sequence.