A power transmission and transformation equipment ice coating disaster monitoring and forecasting method based on meteorological and topographic factors comprises the following steps of: S1, collecting meteorological and topographic data comprising geographic information such as a sea level elevation, river network information, a slope, an exposure, slope variability, exposure variability, a waviness, a roughness, a surface illumination degree and the like; S2, establishing an ice coating thickness estimation meteorological model, wherein the meteorological model is as follows: Y=-0.11x1-0.49x2-0.34x3-0.335x4+0.00x5-0.013x6+0.27x7+1.75x8; S3, carrying out topographic correction of the ice coating thickness estimation meteorological model and carrying out contrastive analysis on an ice coating thickness increment and a difference value of an actually measured value and a meteorological model estimated value, which are obtained by utilizing the formulas, wherein a topographic correction model is as follows: delta Y'=0.19+0.0014x1-0.0035x2+0.045x3; S4, adding the meteorological model in the step 2 with a topographic correction model in the step 3 to obtain a final ice coating thickness comprehensive correction model, completing monitoring on ice coating thickness distribution and carrying out forecasting on the basis of an obtained result. The method considers influence of microtopography and micrometeorology on monitoring of a power transmission and transformation equipment ice coating disaster and has the advantages of high accuracy, high practicality, high reliability and the like.