Abstract: Provided is a biodegradable polyester polymer comprising a polymerization reaction product of an aliphatic dicarboxylic acid, an C6-30 aromatic dicarboxylic acid, an aliphatic diol, and a branching agent, and wherein the biodegradable polyester polymer has a ratio of z-average molecular weight (Mz) to weight average molecular weight (Mw) (“Mz/Mw”) greater than 2 and an easy-tear film including the same. The biodegradable film has excellent mechanical properties to effectively protect a product inside the packaging but also be easily opened in a controlled manner without excessive force and at the same time, provide an environmentally-friendly alternative to non-degradable plastics.