Rational design of efficient, sustainable and low‐cost hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) bifunctional catalysts within the scope of feasibility is of great significance for realizing rapid output water splitting. Here, we used a simple coprecipitation method to prepare Keggin‐type polyoxometalate (POM) nanoscale particles coated with core‐shell‐type metal‐organic framework (MOF) derived Co‐NC (Co‐NC‐POM). Thanks to synergy effect, abundant active sites, unique structure and defects, the as‐synthesized Co‐NC‐POM hybrids exhibit excellent eletrocatalytic performance both for HER and OER. Moreover, it can act as bifunctional electrocatalysts for overall water splitting, exhibiting a low voltage of 1.60 V and an excellently stability up to 24 h at a current density of 10 mA cm−2. It shows competitive performance against the same type of advanced bifunctional catalysts currently reported and thus is expected to among the most efficient non‐precious metal catalysts to drive the water splitting device. [ABSTRACT FROM AUTHOR]