Abstract: The present invention provides a leak-proof portable food and beverage storage container (1000) comprising a box body (200) defining a storage cavity, a lid (400), a ring (600), and a locking mechanism (800). The lid (400) has a groove (410) arranged along edges (420) of the lid (400) and the ring (600) is disposed within the groove (410). The locking mechanism (800) is operationally coupled to the box body (200) and includes a plurality of flaps (810) and a band (820). The plurality of flaps (810) are hingedly connected to the edges (420) and the band (820) is arranged around a rim of the box body (200). Further, the plurality of flaps (810) snap-fits with the band (820) such that the lid (400) is securely fixed to the box body (200) and the ring (600) creates an air-tight seal between the lid (400) and the box body (200).