Longer PD duration, older age-at-study entry and presence of depression were associated with cognitive dysfunction in PD. Heterozygous carrier of G2385R of LRRK2 was found in 7.7% of Parkinson’s disease (PD) patients. There was no association between LRRK2 G2385R genotype and cognitive dysfunction assessed by MMSE Z score or MoCA in PD. The interaction terms between PD duration and the LRRK2 G2385R genotype were not significant for the MMSE Z score. There was an interaction between PD duration and LRRK2 G2385R genotype for cognitive decline assessed by MoCA score in PD.