Hi khushi,listn(or read) you are confused about 2 very different things.
Rate constant is frm kinetics.It is actually a parameter to measure the rate of a reaction ie: how fast or slow a reaction proceeds towards completion.Higher the rate constant, faster the reaction n vice versa.
Equillibrium constant comes in use when you are dealing with reversible reactions in Chemical Equillibrium.While the expression for both the constants may raise the confusion,equi. constant is a measure of how fast the reaction proceeds towards the equillibrium stage(and not towards completion as in rate const.).
Moreover, equi.const.is of two types depending upon the nature of reactants and products while rate constant largely depends upon the order of reaction(Rate law!!?).