An array substrate and an OLED display panel are provided. The array substrate includes a base substrate, a first film layer set and a second film layer set. A bending area of the array substrate has a first trench throughout the first film layer set and a second trench throughout the second film layer set. The first film layer set close to the second film layer set has a blocking part having an etching opening corresponding to the first trench. The etching opening is throughout the blocking part. A bottom of the etching opening connects to a top of the first trench. A bottom of the second trench connects to a top of the blocking part.