The invention discloses a fatty alcohol block polyether with good low temperature stability and a preparation method thereof. The preparation method comprises the following steps: mixing a fatty alcohol and a composite catalyst, purging and replacing with nitrogen, and then removing water; allowing the obtained mixture to react with propylene oxide, and then performing aging, so that an intermediate product is obtained; and finally, allowing the intermediate product to react with ethylene oxide, and then performing aging, so that a final product is obtained, wherein the composite catalyst is amixture of an alkaline earth metal catalyst and tin oxalate. The invention also discloses application of the fatty alcohol block polyether with good low temperature stability as a surfactant. The fatty alcohol block polyether with good low temperature stability has the advantages of low temperature clarification, no delamination, and good emulsifying ability.