Illegal structures along Fedha Road and in Nyayo estate were demolished on Thursday morning, the county saying they were not needed.
Most of the 140 structures, which were put up a few months ago, were kiosks and juakali workshops.
Nairobi Chief Operations Officer Peter Mbaya said the exercise will be extended to Taj mall area, Embakasi East village, Manyanja Road and Buruburu.
Mbaya noted that the city becomes untidy when business people are allowed to set up shot anywhere.
"If we allow people to build illegal structures what kind of Nairobi will we have?” he posed. "These people will go back to wherever they came from. Some came from the rural areas.”
Demolitions took place in Kibera on June 21, but residents who live near the railway line complained, saying they woke up to eviction yet they were to be relocated.
They accused the government of defying a court order and said they will fight any attempts to demolish their houses to pave the way for road construction.
The Kenya Urban Roads Authority is constructing the Sh2 billion Ngong Road-Kungu Karumba-Lang’ata link road, which will reduce traffic jams on Mbagathi Way, Ngong and Lang’ata roads.
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