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The objectives of this study were to measure the chlorophyll fluorescence (ChlF) parameters of Barbula indica (Hook.) Spreng and Conocephalum conicum (L.) Dumort subjected to various light intensities (LI) as a reflection of their adaptability to their habitats. The electron transport rate (ETR) of all plants under 500 μmol m -2  s -1 photosynthetic photon flux density (PPFD) was significantly higher than other LI treatments, implying that these plants could be grown under a specific and optimal light intensity adapted to 500 PPFD conditions. As LI increased from 50 to 2,000 PPFD, we observed in all plants increased non-photochemical quenching (NPQ) and photo-inhibitory quenching (q I ) and decreased photosystem II efficiency (ΦPSII), potential quantum efficiency of PSII (F v /F m ), actual PSII efficiency (ΔF/F m '%), and F v /F m %. In addition, energy-dependent quenching (q E ), the light protection system (q E  + q Z  + q T ), and q I increased as ΦPSII decreased and photo-inhibition% increased under 1000, 1500, and 2000 PPFD conditions, suggesting that these plants had higher photo-protective ability under high LI treatments to maintain higher photosynthetic system performance. B. indica plants remained photochemically active and maintained higher q E under 300, 500, and 1000 PPFD, whereas C. conicum q Z  + q T exhibited higher photo-protection under 500, 1000, and 1500 PPFD conditions. These ChlF indices can be used for predicting photosynthetic responses to light induction in different bryophytes and provide a theoretical basis for ecological monitoring., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)