The utility model relates to greenhouse equipment; an outer arch centre is connected with an outer column and an outer gutter, and an inner arch centre is connected with an inner column and an inner gutter; a conjoined greenhouse with double-thin-film coating is formed, and the covering, such as plastic coating, a sunshade net, etc. are covered on the conjoined greenhouse. The inner and the outer covering can be respectively and independently rolled or put down by corresponding rolling coating mechanism; the rolling and putting down of the coating can be controlled according to different seasons and different time periods of everyday, and temperature control is convenient. In summer, the inner coating and the outer coating can be altered to a sunshade net for achieving the cooling effect, and in winter, the inner coating can be altered to heat preservation coating; the inner coating and the outer coating are all put down for strict covering; the airtight greenhouse with double-thin-film coating is formed; the performances of heat preservation and cold resistance of the greenhouse are enhanced. The inner and the outer gutters are adopted for connecting the arch centre and the fixing the coating covering. On one hand the sealing effect is played, and on the other hand the problems of dewing and water drainage between the double deck coating are solved by the inner and the outer gutters for water drainage. The utility model has simple structure, and belongs to the conjoined greenhouse of energy-saving type.