The present invention relates to the anticancer property studies of a series of chiral palladium N-heterocyclic carbene complexes of the general formula of (NHC)2PdX2 [NHC=chiral N-heterocyclic carbene ligand 1-(1S,2S,5R/1R,2R,5S)-menthyl-4-(R)-1,2,4-triazol-5-ylidene, wherein R=Et, allyl and CH2Ph; X═Br or OCOCF3], as designated by, (1S,2S,5R)-(1-3)b and (1R,2R,5S)-(1-3)b, (1S,2S,5R)-(1, 3)c and (1R,2R,5S)-(1, 3)c represented by formula (Ig, Ih) below. The present invention further investigates the influence of chirality on the anticancer activity, wherein the enantiomeric pairs of present chiral palladium N-heterocyclic carbene complexes of formula (Ig, Ih) shows no differential activity based on optical isomerism despite all of the palladium complexes exhibiting high anti-proliferative activity towards a variety of cancer cells. Also, provided herein is a process of preparation of the chiral palladium N-heterocyclic carbene complexes and a pharmaceutical composition comprising the chiral palladium N-heterocyclic carbene complexes. The present invention relates to the mechanistic details highlighting the mode of action of the chiral palladium N-heterocyclic carbene complex of the formulation for their anticancer application.