为扩大磷石膏的综合利用，以原状磷石膏(RPG)和β-半水磷石膏(HPG)为主要原材料，利用偏高岭土(MK)和碱性激发剂(生石灰、水玻璃)改性制备磷石膏基复合胶凝材料。通过单因素试验探究MK掺量、水玻璃掺量及RPG和HPG的相对掺量对偏高岭土-磷石膏基复合胶凝材料(MKPGBM)力学性能、耐水性能和耐干湿性能的影响，并分析其作用机理。结果表明，MK、水玻璃及HPG掺量的增加均能有效提高MKPGBM的强度。MK和水玻璃掺量(以质量分数计)分别为7%~9%和21%~24%时，MKPGBM的力学性能和耐水性能最优。当RPG与HPG相对掺量(质量分数比)为5∶5时，MKPGBM的28 d抗压和抗折强度最优，分别为19.58和7.44 MPa；当RPG与HPG相对掺量为6∶4时，MKPGBM的综合性能较优，其28 d软化系数达到0.796。MK和掺合料的掺入能有效促进水化产物的生成并填充基体之间的孔隙，还能提高RPG内部颗粒的相互接触强度，进而达到改善磷石膏基复合胶凝材料力学性能、耐水性能及耐干湿性能的效果。

In order to expand the comprehensive utilization of phosphogypsum, raw phosphogypsum (RPG) and β-hemihydrate phosphogypsum (HPG) were used as main raw materials. Besides, metakaolin (MK) and alkaline activators (quicklime, water glass) were used to modify and prepare a kind of phosphogypsum-based composite gelling materials. The effects of MK content, water glass content and the relative ratio of RPG and HPG on mechanical properties, water resistance and dry and wet resistance of metakaolin-phosphogypsum-based composite gelling material (MKPGBM) were investigated by single-factor tests. The mechanism was also analyzed at last. The results show that the strength of MKPGBM can be effectively improved by increasing the content of MK, water glass and HPG. The mechanical properties and water resistance of MKPGBM are optimal when the content of MK and water glass (by mass fraction) are 7%~9% and 21%~24%, respectively. When the relative ratio of RPG and HPG is 5∶5 (mass fraction ratio), the 28 d compressive and flexural strength of MKPGBM are the best, which are 19.58 and 7.44 MPa, respectively. The overall performance of MKPGBM is better when the relative ratio of RPG and HPG is 6∶4, and its 28 d softening coefficient reaches 0.796. The incorporation of MK and admixtures can effectively promote the formation of hydration products and fill the pores between matrix, and can also improve the mutual contact strength of RPG internal particles, thereby improving the mechanical properties，water resistance and dry and wet resistance of phosphogypsum-based composite gelling materials.