Ferrocement is one of the recent methods for repair and strengthening of reinforced concrete members. It can be described as a type of thin composite material made of cement mortar reinforced with wire meshes. The wire meshes are uniformly distributed in continuous layers with relatively small diameters. In this research, an experimental test program consists of eleven RC slab specimens repaired and strengthened by ferrocement layers reinforced by traditional steel reinforcement and steel wire meshes as well as manufactured glass and carbon fiber reinforced polymer meshes. The tested slabs classified in three groups. The first group consists of three specimens as reference slabs. The second group for repaired slabs consists of four specimens. They were loaded first by 80% of the ultimate loads and then cracks were repaired and then additional ferrocement layers with different wire meshes were added. The third group for strengthened slabs consists of four specimens. They were strengthened with additional ferrocement layers with different wire meshes without preloading. Slab specimens were tested under two-point loading and subjected to incremental loads till failure. Performance of the tested slabs such as deflections, cracking and ultimate loads as well as crack patterns were investigated, analyzed and discussed in this research. The test results confirm that repair and strengthening technique using ferrocement layers gives good results. Intertwined manufactured carbon fiber wire mesh gave best results for increasing the flexural capacity of RC slabs.