Plasma arc, a kind of high energy density beam, is proposed as one kind of surface treatments in this paper to improve the adhesive properties of the chromium coatings to the steel substrate. Scratch tests are used to obtain the critical load (Lc) of the coatings. The wear behaviors are evaluated by a reciprocating ball-on-flat wear machine and the wear tracks of the coating were characterized by scanning electronic microscope (SEM). Results show that plasma arc treatment could promote the adhesive and the wear performances of the chromium coatings. Optimal value of Lc and the wear resistance of the treated coatings could be obtained when the average output energy density of the plasma arc (E) grow to 1.05×105J/m2. The comparative study indicates that the promotion of the adhesion could be attributed to the formation of the inter-diffused alloyed layer and the improved hardness distribution. This promotion then contributes to the improvement of the wear performance, which makes up, even exceeds the loss of it caused by the drop of the coatings hardness.