The Cs(7D_J)+H₂→CsH[X¹∑⁺(v″=0)]+H photochemical reaction was studied in a cell experiment by laser pump-absorption technique. Using two-photon exitation of the Cs7²D atomic level in a Cs-H₂vapor mixture,the resulting fluorescence includes a direct component arising from the optically excited state and a sensitized component due to the collisionally populated fine-structure state. The CsH molecules are formed in three-body reactive collisions between exited Cs7²D atoms and ground state H₂ molecules. Nearinfrared absorption band CsH X¹∑⁺(v″= 0 →v′= 21)near 780 nm was measured. The cross sections for the 7D_3/2→7D_5/2 and 7D_5/2→7D_3/2 fine-structure mixing are(1.3±0.3)×10^－14 and(9.8±2.0)× 10^－15cm²,respectively. The cross sections for collisional transfer from 7D_J to states other than 7D for J being 3/2 and 5/2 are(4.0±1.0)×10^－15 and(3.6±0.9)×10^－15cm²,respectively. The reaction cross sections [i.e.,Cs(7D_J)+H₂→CsH+H]for J being 3/2 and 5/2 are(1.4±0.5)×10^－16 and(1.1±1.4)×10^－16cm²,respectively. The relative reactivity with H₂ for two studied atoms is in an order of Cs(7D_3/2)>Cs(7D_5/2).