We report comprehensive angle-resolved photoemission investigations on the electronic structure of single crystal multiple-layer FeSe films grown on CaF_2 substrate by pulsed laser deposition(PLD) method. Measurements on FeSe/CaF_2 samples with different superconducting transition temperatures T_c of 4 K, 9 K, and 14 K reveal electronic difference in their Fermi surface and band structure. Indication of the nematic phase transition is observed from temperature-dependent measurements of these samples; the nematic transition temperature is 140-160 K, much higher than ~90 K for the bulk FeSe. Potassium deposition is applied onto the surface of these samples; the nematic phase is suppressed by potassium deposition which introduces electrons to these FeSe films and causes a pronounced electronic structure change. We compared and discussed the electronic structure and superconductivity of the FeSe/CaF_2 films by PLD method with the FeSe/SrTiO_3 films by molecular beam epitaxy(MBE) method and bulk FeSe. The PLD-grown multilayer FeSe/CaF_2 is more hole-doped than that in MBE-grown multiple-layer FeSe films. Our results on FeSe/CaF_2 films by PLD method establish a link between bulk FeSe single crystal and FeSe/SrTiO_3 films by MBE method, and provide important information to understand superconductivity in FeSe-related systems. We report a comprehensive angle-resolved photoemission investigations on the electronic structure of single-crystal multiple-layer FeSe films grown on CaF_2 substrates by pulsed laser deposition (PLD) method. Measurements on FeSe / CaF_2 samples with different superconducting transition temperatures T_c of 4 K, 9 K, and K display electronic difference in their Fermi surface and band structure. Indication of the nematic phase transition is observed from temperature-dependent measurements of these samples; the nematic transition temperature is 140-160 K, much higher than ~ 90 K for The bulk FeSe. Potassium deposition is applied onto the surface of these samples; the nematic phase is suppressed by potassium deposition which introduces electrons to these FeSe films and causes a pronounced electronic structure change. Wein and discussed the electronic structure and superconductivity of the FeSe / CaF_2 films by PLD method with the FeSe / SrTiO_3 films by molecular beam epitaxy (MBE) method and The results of FeSe / CaF_2 films by PLD method establish a link between bulk FeSe single crystal and FeSe / SrTiO_3 films by MBE method, and provide important information to understand superconductivity in FeSe-related systems.