A UCI transmission method and a mobile terminal are provided, which relate to the field of communication technology and are used for ensuring normal transmission of UCI. The method includes: in a case that at least one of K first time-domain resources aggregated in a time domain on an uplink data channel conflicts with a second time-domain resource on an uplink control channel for carrying UCI, transmitting the UCI on M ones of the K first time-domain resources; K is an integer greater than 1, M is a positive integer less than or equal to K. Normal transmission of the UCI may be ensured by carrying the UCI on at least one first time-domain resource, when a time conflict occurs between time-domain resources aggregated in time domain on an uplink data channel and a time-domain resource on an uplink control channel for carrying the UCI.