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We report comprehensive angle-resolved photoemission investigations on the electronic structure of single crystal multiple-layer FeSe films grown on CaF2 substrate by pulsed laser deposition (PLD) method.Measurements on FeSe/CaF2 samples with different superconducting transition temperatures Tc 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/CaF2 films by PLD method with the FeSe/SrTiO3 films by molecular beam epitaxy (MBE) method and bulk FeSe.The PLD-grown multilayer FeSe/CaF2 is more hole-doped than that in MBE-grown multiple-layer FeSe films.Our results on FeSe/CaF2 films by PLD method establish a link between bulk FeSe single crystal and FeSe/SrTiO3 films by MBE method,and provide important information to understand superconductivity in FeSe-related systems.