Rates of net photosynthesis (PN) and transpiration (E), and leaf temperature (TL) of maintenance leaves of tea under plucking were affected by photosynthetic photon flux densities (PPFD) of 200-2 200 µmol m-2 s-1. PN gradually increased with the increase of PPFD from 200 to 1 200 µmol m-2 s-1 and thereafter sharply declined. Maximum PN was 13.95 µmol m-2 s-1 at 1 200 µmol m-2 s-1 PPFD. There was no significant variation of PN among PPFD at 1 400-1 800 µmol m-2 s-1. Significant drop of PN occurred at 2 000 µmol m-2 s-1. PPFD at 2 200 µmol m-2 s-1 reduced photosynthesis to 6.92 µmol m-2 s-1. PPFD had a strong correlation with TL and E. Both TL and E linearly increased from 200 to 2 200 µmol m-2 s-1 PPFD. TL and E were highly correlated. The optimum TL for maximum PN was 26.0 °C after which PN declined significantly. E had a positive correlation with PN. and T. S. Barman, U. Baruah, J. K. Saikia.