The invention discloses a method for increasing melting temperature of Fischer-Tropsch wax. The method comprises steps as follows: step one, the Fischer-Tropsch wax and a solvent which is 0.02-5.0 times the weight of the Fischer-Tropsch wax are mixed in a liquid state, a mixed solution is cooled and solidified in 1-24 h, and a crystallized mixture of the Fischer-Tropsch wax and the solvent is obtained; step two, the crystallized mixture of the Fischer-Tropsch wax and the solvent remains at constant temperature of 30-120 DEG C for 2-24 h, part of the crystallized mixture of the Fischer-Tropschwax and the solvent is melted, and the un-melted crystallized mixture and the melted crystallized mixture are separated; step three, the Fischer-Tropsch wax and the solvent in the un-melted crystallized mixture are separated, the Fischer-Tropsch wax with high melting temperature is obtained, the Fischer-Tropsch wax and the solvent in the melted crystallized mixture are separated, the Fischer-Tropsch wax with low melting temperature is obtained, and the solvent is recovered and recycled. The method has the advantages as follows: high temperature and high vacuum degree are not needed, energy issaved, the hidden danger of adverse effect of the high temperature on performance of the Fischer-Tropsch wax is avoided, no three wastes are produced, and the Fischer-Tropsch wax in different meltingtemperature ranges can be obtained as required.