The present disclosure relate to affine inheritance method in intra block copy mode. A method for video processing is provided, including: in a process of acquiring motion information of a current video block, during a conversion between the current video block and a bitstream representation of the current video block, wherein the motion information of the current video block is based on at least one affine model of at least one neighboring block of the current video block, determining whether a neighboring block of the current video block uses an Intra-Block Copy (IBC) mode in which at least one reference picture used by the neighboring video block is identical to a picture in which the neighboring block is located; disabling, for the current video block, to derive an affine candidate from the neighboring block based on determining that the neighbouring block uses the IBC mode; and performing the conversion based on the motion information of the current video block.