Provided are thermoplastic polymer particles having an aspect ratio of 1.00 or more and less than 1.05, and a roundness of 0.95 to 1.00. The thermoplastic polymer particles are formed from a thermoplastic polymer resin in a continuous matrix phase. The thermoplastic polymer particles show a peak cold crystallization temperature (Tcc) at a temperature between a glass transition temperature (Tg) and the melting point (Tm) in a differential scanning calorimetry (DSC) curve which is derived from temperature rise analysis at 10° C./min by differential scanning calorimetry.