Paleoenvironmental studies in New Caledonia allow to characterize guano records as high- resolution environmental archives. The first results of a multidisciplinary guano studies (pollen, 13C, D and n-alkane, Wirrmann et al., 2015 ; Sémah et al., 2016 ; Wirrmann et al., 2016; Wirrmann et al., 2017) highlight the link between strict environmental parameters and predator’s diet. Among the several disciplines used to reconstruct the environment from guano, paleoentomology is not usual. Poverty of theses studies are explained by the taxonomic complexity of the high fragmentation rates, and lack of ecological data about endemic species in tropical environment. Here, we test the validity of paleoentomological analysis as new environmental proxies. Two kinds of guano were studied: that of the salanganes, Collocalia spodiopygia, insectivorous and diurnal and from bats, Micropterus robustior, insectivorous and nocturnal. To overcome difficulties, we developed unconventional technical and statistical methods in paleoentomology (Rollin, 2017). First, taxonomically identified insects were used as bioindicators and calibrated statistically with palynological and isotopic data to identify climatic parameters during guano accumulation. Secondly, metabarcoding analysis complements the taxonomic method and identifies the metagenomics perspectives in this context. The last method consists in infrared spectroscopy analysis (SWIR) of chitinous remains. The analysis could reveal relationships between the different guano samples. The results show the possibilities offered by the conjunction of these methods. Pluridisciplinary studies initiated by LOCEAN UMR and the plant/insect associations makes it possible to identify the seasonality and the origin of the environmental changes. Finally we propose the use of these methods as proxy for paleoenvironmental reconstitution based on cave guano studies, to the benefit of the scientific communities.