Micro-seismic monitoring,as a technique for the design,implementation and evaluation of hydraulic fracturing volume reformation,has been developing rapidly with the large-scale development of unconventional hydrocarbon reservoir.The sand-gravel reservoir in Yan227 wellblock of Dongying sag has low porosity and very low permeability. Based on micro-seismic monitoring data acquisition and processing of Well Yan227-3HF and Well Yan227-8HF,the development of artificial fracture space,including its length,width,direction and height,and its effective rang were analyzed at first through the methods of vertical projection of micro-seismic event point,side projection,calculating of fracturing volume and fracturing frontal area,etc. And then data from drilling,logging,well logging,3D seismic and fracturing construction process parameter curve were comprehensive utilized,thus the characteristics of natural fracture distribution,the lithology and sedimentary facies belt of each fracture section and their influence on spatial distribution of artificial cracks were analyzed. Finally,the unconventional hydrocarbon reservoir fracturing effect was evaluated comprehensively in Yan227 well? block area. The results show that the middle-fan section is easier to be fractured compared with the fan root; pebbly sandstone with relatively thick layer has better fracturing effect than the one with thinner layer and multi-interbedded mudstone.