The work aims to study and develop spray polyurea elastomer to be used on the surface of wooden voice box, expand application field of spray polyurea elastomer, and meet the demand of surface protection and elegant coating of the wooden voice box. The spray polyurea elastomer was prepared mainly from isocyanate (as A component) as well as polyether polyols and amine chain extender (B component) in high-pressure airless spraying method. The effects of such factors including isocyanate content, chain extender type and volume and polyether polio on properties including gel velocity, hardness, elongation and appearance of polyurea were discussed. Polyurea products applicable to surface painting. Physical performance and medium resistance tests were performed to spraying polyurea products. Proper isocyanate content of spray polyurea elastomer was determined as 18%~24%. Finally, isocyanate content was defined as 21%. Construction and appearance requirements could be met when weight ratio of selected chain extender 1 versus extender 2 was 2:1. Proper weight ratio of PPG2000 versus TMN3050 was 1.6:1, which can achieve both rigid and tough characteristics. In addition, physical performance and medium resistance tests performed to spray polyurea showed that both properties were favorable. The spray polyurea elastomer applicable to surface of wooden voice box was developed and studied successfully. The results show that the spray polyurea elastomer exhibits favorable mechanical strength and decoration performance. Furthermore, practical application and spraying technique are introduced. The practical application shows that the material could have a very good decorative and protecting effects on the surface of voice box.