TO PROVIDE A GUAVA LEAF EXTRACT POWDER WHICH EXHIBITS LESS DEETERIORATION IN QUALITY AND FUNCTIONS AFTER STORAGE OF THE SOLUTION THEREOF FOR A LONG PERIOD OF TIME. THE INVENTION PROVIDES A METHOD FOR PRODUCING A GUAVA LKEAF EXTRACT POWDER, INCLUDING EXTRACTING GUAVA LEAVES WITH HOT WATER AT 90 TO 98°C; CONCENTRATING THE OBTAINED EXTRACT TO A BRIX LEVEL OF 20 TO 30; AND LYOPHILIZING THE CONCENTRATED EXTRACT, AND A GUAVA LEAF EXTRACT POWDER PRODUCED THROUGH THE METHOD.