Installation with sunlight and holography, as environmental art, is presented. I exhibited the out door installation with holography at Villa dei Quintili where is located in the remains of ancient Roma in 2007. My first outdoor artworks involving hologram was created in 1979. In the white light reconstruction hologram, a direct sunbeam is the ideal reconstructing light source. In sunny weather, a hologram reconstructs bright images, irrespective of the brightness during the day. On the other hand, during cloudy or rainy weather, there is no image because scattered light does not reconstruct the image. Sunlight opens a hologram from darkroom and artificial illumination. The out door works with holography involved sunlight changes in response to the influence of the weather and time. Such work that changes in response to environment surrounding a work, natural environment and especially the sunlight, presents a completely new concept to environmental art field. In this paper, I describe several practice of installation with sunlight and holography that I had done until now.