Taking the biogas reservoir in the Rakhine Basin sea area, Myanmar as an example, through geochemical, seismic forward modeling, sedimentology theoretical and examples comparison methods, summarized three factors of biogas reservoiring, then designat⁃ed exploration orientation. (1) Relied on geochemical analysis and comparison of known geological living cases, proposed biogas source rock“three lows and one high weak lithogenesis”*geological characteristics. Specified the Pliocene mudstone, Miocene mudstone and canyon mudstone have the condition to form biogas source rocks;while mudstone above Pliocene mudstone not. (2) From oil and gas thermal genesis theory, combined with seismic forward modeling sections, using gas dynamic equation for equilibrium flows, analyzed their migration and accumulation factors, provided hydrocarbon expulsion model and favorable accumulation area seismic response characteristics. (3) Combined with Rakhine sea area actual geological condition, through gravity flow sedimentation theory, carried out experiment analysis for single well samples, provided reservoir, cap rock assemblage and cap rock evaluation criterion for deep water gravity flow sedimentary system. Through the single well case has found three main types of lithologic hydrocarbon reservoir in Rakhine sea area, Myanmar, and proposed the lithologic seismic anomalous reflection area with structural setting is significant exploration orien⁃tation for biogas reservoir in the area.%以缅甸若开盆地海域范围内的生物气藏为实例，通过采用地球化学、地震正演建模、沉积学理论、实例比对等方法，总结出生物气成藏三大因素，进而指明勘探方向。（1）依托地化分析及已知地质实例比对，提出生物气烃源岩“三低一高弱成岩”的地质特征，明确上新统泥岩、中新统泥岩、峡谷泥岩具备形成生物气的烃源岩条件，而上新统之上的泥岩不具备形成生物气的烃源岩条件；（2）对比热成因油气理论，结合地震正演剖面，采用气体动力平衡方程，分析其运聚因素，给出排烃模式及有利聚集区的地震响应特征；（3）结合海域实际地质情况，利用重力流沉积理论，对单井样品进行实验分析，给出深水重力流沉积体系下的储盖组合及盖层评价标准。通过单井实例，获得缅甸若开海域岩性油气藏的三种主要类型，提出具有构造背景的岩性地震异常反射区是该区生物气藏重要的勘探方向。
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