To obtain a flame retardant polyketone resin composition capable of exhibiting a high flame retardancy, excellent fluidity and molding processability and capable of forming an article having high impact resistance by compounding a specific amount of a specific magnesium hydroxide particles to a polyketone resin.

This flame retardant polyketone resin practically includes (A) 40-85 wt.% of a polyketone and (B) 15-60% of magnesium hydroxide particles having 1-15 m2/g of specific surface area measured by BET method, average particle size of 0.2-5 μm and the surface covered with a surface treating agent. The preferable component A has a main chain comprising repeating units of formulas I and II (D is an alkylene chain except ethylene chain) in a mole ratio (formula II/formula I) 0.01-0.2. The preferable surface treating agent for the component B is a phosphate ester of formula III (R is a 1-24C alkyl or the like; A is a 2-4C alkylene; n is 0-6; m is 1 or 2; M is a cation such as alkali metal or the like). A polyketone resin composition suitable for various molded articles is provided.