A separating device (100) for separating insects (204) from a rearing-based material (202, 203) includes a sieve part (110) and a moving part (280) for moving the sieve part in order to sieve an unseparated material (201). The unseparated material includes the insects and the rearing-based material. The sieve part includes an cylindrical sieve rotor (110) and the moving part is adapted to rotate the rotor in order to separate the insects from the rearing-based material. The rotor is inclined so that its lower end (112) is lower than its upper end (111).
