The invention discloses a daylighting heat preservation device suitable for a steel-structure factory. The daylighting heat preservation device comprises a base and a connecting frame, wherein a second connecting plate is arranged below the base, a second installing hole is formed in the upper surface of the second connecting plate, a first connecting plate is arranged above the second connectingplate, a structural base plate is arranged in the first connecting plate, and a heat preservation layer is arranged above the structural base plate. According to the daylighting heat preservation device suitable for the steel-structure factory, a plurality of light-transmitting holes are formed in the upper surface of a protective net and are uniformly distributed on the surface of the protectivenet. When a daylighting plate is put above protrusions, the daylighting plate is attached to the light-transmitting holes, and the number of the light-transmitting holes is large, the daylighting plate is made of a transparent material, so that daylighting area is larger, the daylighting effect in the factory is better. The protrusions are arranged above the connecting frame, penetrates through the connecting frame and play a supporting effect, so that the connection between the daylighting plate and the connecting frame is more stable and firmer.