In the present core drilling project， there are still some problems such as low core recovery rate and low coring efficiency in broken formations. In this paper， the broken strata are classified into hard broken， soft broken， brittle broken and loose broken according to the lithology and broken reasons. The problems of core erosion， blocking， grinding and loss are analyzed. It is thought that the main reasons to coring problems in broken areas are as follows， in the hard broken strata， the core tube is blocked due to the core broken and vollume increase， in the loss broken strata， the drilling fluid erodes the cores， which both exist in the soft broken and brittle broken strata， moreover， it is not easy to be discovered because of the high drilling speed. The contermeasures are as follows： coring technology of low WOB， low RPM， low pump pressure and high performance water-based polymer drilling fluid， anti-erosion core bit， compound core claw， and double pipe single action wireline coring tool. The relevant technology was applied in ZG1 coal seam coring in Songjiaying south comprehensive gas survey， Tangshan City， Hebei Province， and the core recovery rate in the coal seam was reached to 98.77%， which has certain referential value to core drilling in similar strata.