The invention provides a memory card detection circuit of a computer. The memory card detection circuit comprises a plurality of query pins through which a memory card is coupled to the computer and a plurality of latch circuits respectively coupled to each of the query pins. The latch circuits generates query signals indicating whether ground bounce occurs in the voltage of the query pins due to a voltage difference between two ends of the query pins shortly after the memory card is coupled to the computer through the query pins. The query signals identify the type of the memory card without waiting until ground bounce is resolved.