The invention discloses a method for restoring a mine matrix and greening by utilizing microalgae artificial biological crusts, which comprises the following steps of: A, in a mine reclamation area in which plants are difficult to grow, selecting sand, transporting the sand to a region to be repaired and paving the sand; B, planting grasses to carry out greening, i.e. selecting herbaceous plants growing in a mine to plant; C, carrying out shrub greening, i.e. using salix psammophila, artemisia songarica schrenk, caragana microphylla and astragalus adsurgens which grow in drought-resistant regions, selecting poplar, oleaster, pines and cypress which belong to arbor, and planting shrub such as salix psammophila; D, carrying out artificial crust treatment; E, carrying out watering maintenance; and F, checking the microalgae biological crusts, wherein the step D of carrying out artificial crust treatment comprises a step a of selecting an algae type, a step b of preparing algae culture solution and a step c of culturing algae; and the step c of algae culture comprises the following steps of: (1) primary culture, (2) secondary culture, (3) tertiary culture, (4) culture of a runway-type impeller stirring and circulating culturing pool, (5) biomass collection of the algae and (6) inoculation of the microalgae artificial biological crusts. The method is easy to implement and is convenient to operate; and an effective method is provided for mine restoration, ecological restoration and improvement on the ecological environment.