Abstract: When aircraft traverse ice crystal-laden clouds, ice crystals may be ingested into the engine with the airflow, leading to ice accretion that jeopardizes flight safety. To investigate how the melting state of ice crystals affects their adhesion and ice accumulation characteristics, numerical simulations and experimental studies were conducted on the melting process of ice crystal particles under suspended conditions. Our findings indicate that the melting process of ice crystals can be divided into solid phase and ice-water mixture phase, whose corresponding theoretical models have been formulated. The influence of air temperature, environmental humidity, initial ice crystal temperature, and initial ice crystal diameter on ice crystals' melting rate, mass loss rate, and temperature was assessed. Through orthogonal test analysis, the degree of influence of various factors on ice crystal melting has been determined as follows: air temperature has the greatest impact, followed by initial ice crystal diameter, then relative humidity, and finally initial ice crystal temperature. An ice crystal suspension melting experiment platform was set up to further study the effects of the initial particle size of ice crystals, ambient temperature, and relative humidity on the melting rate and complete melting time. The comparison between numerical and experimental results indicates that the relative error of complete melting time is less than 25%, with 83% of these errors falling within the range of –20% to 20%; the relative error of the particle size is within 5%. This study sheds light on the mechanism of ice crystal melting phase transition, offering valuable insights that can serve as both a theoretical and experimental reference for the research on aircraft ice crystal icing.