Embodiments of mechanisms of a wafer pod including a wafer positioning mechanism are provided. The wafer positioning mechanism includes a base including a blocking portion, and a linking bar pivoted on the base and including a resilient portion. The wafer positioning mechanism also includes a pushing element pivoted on the linking shaft. Further, when the pushing element is at a retaining position, the resilient portion abuts against the blocking portion, and a force generated by the linking bar is applied to the pushing element.