Some demonstrative embodiments include devices, systems and methods of offloading traffic of a Secondary Cell Group (SCG). For example, some embodiments may include identifying a SCG bearer that is offloadable to the Internet via a Network Address Translation (NAT) gateway, based on offloading information received from a Master Evolved Node B (eNB) (MeNB); and offloading uplink Internet Protocol (IP) packets of the SCG bearer to the Internet via the NAT gateway, if the SCG bearer is indicated to be offloadable.