The application belongs to the field of roof waterproof protective layer, and particularly discloses a roof waterproof protective layer construction method based on microbial concrete, and the specific steps are as follows: S1, microbial culture; S2, protective carrier wrapping; S3, concrete preparation; S4, concrete pouring; and S5, concrete curing; the method uses expanded
perlite particles as carrier medium, and respectively immobilizes single bacillus and aerobic mixed
bacteria, so that the single bacillus and the aerobic mixed
bacteria are activated at the same time when cracks are formed, and a composite mineralized structure is induced to form, the repair effect of the cracks is enhanced, the high strength of
aragonite and the good filling property of
calcite are combined, the overall strength and durability of the crack repair area can be improved, the
visual appearance of the concrete repair area is increased, the expanded
perlite particles are used as carrier medium, and the hydrogel wrapped on the surface of the bacterial expanded
perlite can protect the microorganisms and be used as a
water storage agent, and the survival environment of the microorganisms is enhanced.