The invention relates to a cefoperazone sodium-sulbactam sodium eutectic crystal and a pharmaceutical composition containing the eutectic crystal, and preparation methods thereof. The cefoperazone sodium-sulbactam sodium eutectic crystal has the advantages of concentrated distribution of crystal form grain size, good product fluidity, gloss surface, high degree of crystallinity and good stability; the preparation method of the crystal form is simple in process, easy to operate, and suitable for popularization and application in a wide range. In the compound cefoperazone sodium-sulbactam sodium preparation, through introduction of the cefoperazone sodium-sulbactam sodium eutectic crystal and a phosphate buffer to adjust the pH value, the problems that a mixed powder in the preparation is poor in uniformity, liquidity and raw material stability are solved, generation of carbon dioxide gas due to addition of a stabilizer carbonate is avoided, an obtained powder injection is diluted through conventional transfusion, then dissolved rapidly and does not produce crystallization and degradation products, the solution clarity is in accordance with provisions, the solution pH value has no obvious change, and the contents of cefoperazone sodium and sulbactam sodium are stable.