Our previous research demonstrated that Etlingera elatior possesses whitening and anti-aging properties and also contains bioactive ingredients for cosmeceuticals. Therefore, this research work aimed to evaluate the efficiency of whitening cream containing both the flower and leaf extracts of E. elatior in human volunteers and their degree of skin irritation. Both the flower and leaf extracts were formulated as a cosmetic called “FL1 cream”, which was assessed for its physical properties and underwent an accelerated stability test. The FL1 cream was also evaluated for skin irritation and its skin whitening effect among 24 healthy volunteers who used it for four weeks. The FL1 cream demonstrated good physical stability under the various conditions for three months, along with six cycles of heating/cooling. The irritation analysis showed that irritation reactions were absent in all volunteers. The efficiency of FL1 cream in improving the appearance of skin whitening was demonstrated by a significant (p < 0.05) and continuous decrease in melanin content compared with the initial value. Additionally, the L* value was significantly and continuously increased after application of the FL1 cream. The highest melanin reduction was 6.67%. The FL1 cream containing E. elatior extracts can be used as a whitening cream in cosmetics.