This paper aims to investigate how different intensities of language contact affect the process of phonological simplification. We conducted a sociolinguistic rapid and anonymous survey in Shanghai to collect information on along a bus route. The results show that area of residence has a significant effect on the merging result. The merger rate is higher in peripheral areas where language contact is more intensive than in central areas where language contact is less intensive. We therefore argue that the intensity of language contact affects the process of phonological simplification. The higher the intensity, the faster the phonological simplification.