A composite structural material and pharmaceutical composition comprising same, the use of the composite structural material in preparing a sustained release formulation, and a pharmaceutical composition formulation method; the composite structural material comprises a hydrophobic structural material and a hydrophilic structural material; the proportion of the hydrophobic structural material to the hydrophilic structural material ranges from 1:0.01 to 1:5, preferably 1:0.05 to 1:4, more preferably 1:0.1 to 1:3, and most preferably 1:0.4 to 1:2, such as 1:0.4 to 1:1.3. The pharmaceutical composition comprises the composite structural material and one or more active pharmaceutical ingredients, and preferably the proportion of the composite structural material to the active pharmaceutical ingredients ranges from 1:0.01 to 1:8, more preferably 1:0.02 to 1:5, and most preferably 1:0.03 to 1:1, such as 1:0.3 to 1:0.7.