The current study aims to analyze the influence of personality on OCB and OCB-mediated performance among members of the Indonesia National Police, especially investigators and criminal Units of East Nusa Tenggara Regional Police, Indonesia. The samples were 183 police investigators in 3 Directorate of Criminal Investigation. The analysis was conducted quantitatively using mediation regression with Macro Process Hayes SPSS Version 23. The results showed that (1) personality has a positive and significant direct effect on police performance,(2) OCB has a positive and significant direct effect on police performance, and (3) OCB mediates indirectly, and positively significant between personality and police performance.