In present paper the influence of nano-SiC particles on the flux pinning of YBa2Cu3O7-y has been studied. The investigation reveals that nano-SiC does not change the superconducting transition and the microstructure of the superconductors. At a temperature of 5 K the addition of 0.5 and 1 wt% nano-SiC can lead to an additional flux pinning effect and improve evidently the critical current density Jc. For composites with 1 wt% nano-SiC Jc is two times larger than the reference sample. Meanwhile, at temperature of 20 and 50 K, the fishtail effect is observed for composites YBa2Cu3O7-y/nano-SiC. A reasonable interpretation of the enhanced flux pinning and the occurrence of the fishtail effect is given.