[Objective] Black soil of Northeast China suffered serious degradation due to intensive farming in the past decades. To protect Black soil, conservation tillage is encouraged to be applied in this region. However, some studies have reported that this practice may reduce crop yield. Thus, our objective is to evaluate the suitability of conservation tillage and deep tillage in Black soil of Northeast China.[Method] We collected 543 yield comparisons from 61 papers published in international and domestic journals. After synthesis and grouping of required data, we analyzed the impacts of conservation tillage and deep tillage on crop yield and their influencing factors using meta-analysis as well as random-forest methods.[Result] Overall, crop yields were slightly increased under conservation tillage(+1.21%), but significantly enhanced under deep tillage(+12.3%) as compared with traditional rotary tillage. Conservation tillage caused a higher yield only at Liao River Plain(14.6%), whereas deep tillage increased yield by 10% across three plains including Sanjiang, Songnen and Liao River. Under conservation tillage, the yield effect size was most influenced by the mean annual temperature(20% contribution), mean accumulated temperature >10℃(19% contribution) and aridity index(16% contribution). For deep tillage, the most important factor was the topographic slope(14% contribution). Also, conservation tillage increased soil organic C mainly in the top layer and when combined with straw mulching reduced soil temperature remarkably and increased soil moisture. This observation was the main reason for yield reduction under this practice. Deep tillage reduced soil bulk density and penetration resistance significantly, leading to an increase in crop yield. After synthesizing the yield effect size and factor contribution, our results indicated that wind erosion sensitive regions such as western Liaoning and Jilin provinces as well as eastern Inner Mongolia are highly suitable for conservation tillage. On the other hand, the cold, humid, low-lying areas are more suitable for deep tillage, e.g., Sanjiang Plain and the typical Black soil belt.[Conclusion] This study evaluated the suitability of tillage practices in the Black soil of Northeast China based on the effect size of tillage on crop yield. The synthesized results suggest that conservation tillage is more suitable for dry and wind erosion sensitive regions or slopping lands where it can increase crop yield and protect soils as well.