Abstract: Geology radar, which is widely used in the geological prospecting investigation, is employed in shallow geological survey to fractured zone, detect faulted zone, rich water region and karst caves.Combined with advanced geological forecast work of Miyaluo tunnel the reflection characteristics of radar wave pass through unfavorable geological condition are analyzed.In tunnel construction, the method can correctly predict unfavorable geological bodies and rock body structure in front of working face.It can provides effective instruction for practice to ensure construction safety.