The　aim　of　this　paper　is　to　propose　the　concept　of　the　interval-valued　least　square　prenucleolus　of　interval-valued　cooperative　games　and　develop　a　direct　and　an　effective　simplified　method　for　solving　a　special　subclass　of　interval-valued　cooperative　games.　In　this　method,　through　adding　some　conditions,　the　least　square　prenucleolus　of　cooperative　games　is　proved　to　be　a　monotonic　and　non-decreasing　function　of　coalitions＇　values.　Hence,　the　interval-valued　least　square　prenucleolus　of　coalition　size　monotonicity-like　interval-valued　cooperative　games　can　directly　obtained　via　determining　its　lower　and　upper　bounds　by　using　the　lower　and　upper　bounds　of　the　interval-valued　coalitions＇　payoffs,　respectively.　Thus,　the　proposed　method　may　overcome　the　issues　resulted　from　the　Moore＇s　interval　subtraction　and　the　partial　subtraction　operator.　Examples　are　used　to　illustrate　the　proposed　method　and　comparison　analysis　is　conducted　to　show　its　applicability　and　superiority.　Moreover,　some　important　properties　of　the　interval-valued　least　square　prenucleolus　of　coalition　size　monotonicity-like　interval-valued　cooperative　games　are　discussed.