The invention relates to a sustained release microsphere medicinal preparation using PHBHHx as a carrier and a method for preparing the same. The invention discloses a method for preparing the sustained release microspheres by using PHBHHx as a raw material, and by the method, the microspheres having the function of slowly releasing medicaments can be obtained. The method mainly comprises the following steps: dissolving and/or mixing and suspending and/or emulsifying and dispersing medicaments in an organic solvent solution of PHBHHx, and then emulsifying the solution in a water phase to form emulsion; and removing an organic solvent in the emulsion by volatilization to form skeleton type micro spherical entities. The sustained release microsphere medicinal preparation prepared by the method has the advantages of gradually releasing the medicaments in vivo, prolonging medicament effect and making the medicament effect reach the sites difficultly treated by the medicaments; when the sustained release microsphere medicinal preparation is applied in medicinal industry, the peak-valley phenomenon caused by intermittent administration and uneven dose can be eliminated, the medicament concentration or blood medicament concentration on the target sites can be stably controlled for a long time, the biological utilization rate of the medicaments is improved, small dose can achieve the curative effect, the side effect is lowered, and the curing effect is improved; and the quick metabolism of the medicaments is avoided, and the in vivo half-life time of the medicaments is prolonged.