This study investigated the effectiveness of Ultra-High performance-strain hardening cementitious composite (UHP-SHCC) systems for strengthening reinforced concrete (RC) rectangular deep beams which are critical in shear. The experimental program involved two reference control specimens and five strengthened deep beams tested under four-point bending for assessing the effect of shear reinforcement on the behaviour of RC deep beams, the effect of prefabricated UHP-SHCC plates, strengthening techniques (prefabricated or cast in-situ), and UHP-SHCC configuration on the load and deformational capacities of the strengthened specimens. Experimental results revealed that existing of shear reinforcement exerts a major significant contribution to shear strength capacity due to confining struts. The results also ensured the effectiveness application of the UHP-SHCC in enhancing the load capacities (Pmax) of deep beams. The average enhancement of the load carrying capacity achieved by UHP-SHCC strengthening with respect to the un-strengthened specimen is approximately 64%. Continuous strengthening significantly enhanced the structural performance of the strengthened specimens compared to those of the intermittent counterpart. Furthermore, the effect of changing the strengthening technique of the UHP-SHCC strengthening systems used in this study was detected to be insignificant on the load carrying capacity of the strengthened beams.