A lens holder including a base, a gate mark and a tubular portion is provided. The base includes a plurality of sidewalls, and any two adjacent sidewalls are connected to each other to form an outer edge. A turning corner is formed between every two adjacent sidewalls, and the base includes a chamfer located at a turning corner. The gate mark is disposed at the chamfer. The tubular portion is connected to the base, and the tubular portion extends along the direction away from the base. Besides, a portable electronic device and a manufacturing method of the lens holder are also provided.