Guano are accumulations over time of materials issued from bat excretions. Although they constitute potential archives of past environmental changes, they are yet unexplored, at least from an organic geochemistry point of view. Here we discuss biomarker imprints from 15 guano samples recovered from various French caves. Our results are discussed in terms of source of biomarkers, conditions of preservation (guanos constitute a hotspot of acidic conditions in carbonate caves) and mechanisms of transfer of molecular biomarkers from their source to the guano deposit. Samples were collected from guano layers or guano cores recovered from eight caves located in southern France. Miguro (MIG-013 and MIG-014; ~5500 yrs cal BC), Escalans (ESA-19 and ESCA-20; from 4400 to 6000 yrs cal BC), Demoiselles (Demoi-004; dating in progress) and Brouzet (BROU-3; dating in progress) are located in Hérault. Tourtouse (TOURT-1, TOURT-5 and TOURT-10; recent) and L'Herm (Lherm-4, Lherm-8 and Lherm-11; dating in progress) caves are located in Ariège. Fées (FEES-001 and FEES-003) and Roquette (ROQ-002) caves are located in Gard. The age of samples ranges from recent to > 45000 yrs BP. n-Alkanes were abundant (from 2 to 36μg/g) in all samples except ESCA-19 and ESCA-20 and MIG-013 (<1 μg/g). They range from n-C11 to n-C37 with a maximum at n-C29, an Average Chain Length comprised between 27 and 29.5, and a clear odd-over-even predominance (Carbon Preference Index from 2 to 8) except for Lherm-8, MIG-013 and MIG-014, FEES-001 and FEES-003 and ESCA-20. These criteria are typical for n-alkanes derived from vascular plants. In addition, high CPI indicate that in most cases n-alkanes did not suffer strong alteration. The contribution of vascular plant material to the guano is also attested by abundant and diverse C-3 oxygenated pentacyclic triterpenes that indicate and input from angiosperms. β- and α-amyrins and amyrenones, taraxerone were found in all Lherm samples, in MIG-013 and in TOURT-1. Friedelin was detected in BROU-3, Demoi-004, and ROQ-002. Miliacin, a pentacyclic triterpene methyl ether reputed specific of Gramineae (Jacob et al., 2005) and in certain cases of Panicum miliaceum (Bossard et al., 2013) was detected at low abundances (0.1 μg/g) in BROU-3 and ROQ-002. ESCA-19, Lherm-8 and Lherm-11, TOURT-1, TOURT-5 and TOURT-10 contained low levels (<0.2 μg/g) of triterpenyle acetates (β- and α-amyrenyl, germanicyl, bauerenyl and iso-bauerenyl) that are related to Asteraceae (Lavrieux et al., 2011). These compounds are relatively rare in sediment samples and their source could be defined at the genus or species scale if compared to the local plant inventory. Despite harsh acidic conditions, it is worthwhile noting that rearranged pentacyclic triterpenes such as those bearing a bauerane skeleton are still present. The clear angiosperm biomarker imprint in guano samples questions their source and mode of transportation from the source to the deposit. Guano samples are mainly composed of insect remains since bats in temperate areas are exclusively insectivores. Although n-alkane with a distribution mimicking that of vascular plats was found in insect cuticles and attributed an insect origin (Chikaraishi et al., 2012), the presence of C-3 oxygenated pentacyclic triterpenes argues for an angiosperm origin. As such, we conclude that both n-alkanes and pentacyclic triterpenes were first transferred from plants to insects that were then predated by bats, which finally excreted in caves. As such, molecular biomarkers archived in guano archives could reveal efficient descriptors of past vegetation and, by means of compound-specific hydrogen isotope analyses, of past hydroclimates.