The present invention relates to a liquid cleaner for a semiconductor substrate on which metal wiring may be provided, comprising each component of a chelating agent or a salt thereof shown by the following general formula (1), an alkaline compound and pure water, wherein pH is 8 to 13: (wherein, Y1 and Y2 are lower alkylene groups, n is an integer of 0 to 4, at least 4 of R1 to R4 and n R5s are alkyl groups having phosphonic acid group(s) and the rest are alkyl groups) and a cleaning method using the same. The present invention provides a liquid cleaner which can efficiently remove fine particles or impurities derived from various metals at semiconductor substrate surface, even when used after a process adopting an alkaline polishing agent or alkaline etching liquid, without generating problems of causing difficult-to-remove gelled particles at the substrate surface or easy generation of rough semiconductor substrate surface, and a cleaning method using the same.