A card connector includes a main housing having a base portion, a pair of side walls and a bottom wall connecting with the base portion and side walls thereby defining a receiving cavity. Multiple groups of contact sets comprise at least one grounding contact. The contact sets have contacting portions projecting into the receiving cavity. A metallic shell covers a top side of the main housing and defines an insertion opening together with the main housing. A pair of guiders are floatably assembled on opposite sides of the insertion opening for guiding different sized cards. A grounding plate which is attached to a bottom side of the main housing, comprises a pair of flexible tangs respectively pressing against a bottom side of the guiders. The grounding plate further comprises a grounding section electrically contacting with the at least one grounding contact so as to establish a grounding path.