The synthesis and characterization of mononuclear Pd(I) aryl complexes as well as their reactions with organic halides have been studied. The reactions of [(IPr)PdCl2]2 with the m-terphenyl lithium salts LiAr Trip -R-p in Et2O are found to yield the two-coordinate Pd(I) aryl complexes [(IPr)Pd(Ar Trip -R-p)] (R = H, CF3) in moderate yields. These Pd(I) aryl complexes are the rare examples of isolable mononuclear Pd(I) complexes featuring X-type co-ligands. Reactivity studies on their reactions with organic halides disclosed their ability in mediating C(aryl)-I, C(alkyl)-I, and C(benzyl)-Br bond cleavage, among which the reactions with para-substituted benzyl bromides yield cross-coupling products ArCH2-Ar Trip -CF3-p in moderate yields. Mechanistic studies by kinetic experiments, radical trapping reactions, as well as theoretic studies have collectively revealed a stepwise oxidative addition-concerted reductive elimination pathway for these cross-coupling reactions.