Smoke from illegal forest fires in Indonesia has been drifting over Singapore for the past few days causing the haze.
It gave an atmospheric orange tint to the moon for the Mooncake festival held this weekend but many Singaporeans suffered respiratory problems and preferred not to venture outdoors.
The PSI (Pollution Standards Index) has dropped from a high of 150 (unhealthy) on Saturday evening to just 31 (good) on Sunday morning.