Abstract: When laying pipelines under road, railway, river and other obstructions, conventional drenched pipe burying method is hard in construction. DZ-1 small -sized directional drilling newly developed by China Petroleum Pipeline Scientific Research Institute provides an advanced method for laying of various pipelines. The equipment applies high voltage jet drilling process, with characteristics of high drilling efficiency, simple structural drilling tool and reasonable design. In two field tests, three directional holes are drilled successfully. Introduces in detail the on-site test and practical application.