Ministry of Megapolis and Western Development (Sinhala: මහානගර හා බස්නාහිර සංවර්ධන අමාත්‍යාංශය Mahanagara Ha Basnahira Sanvardhana Amathyanshaya) was an appointment in the Cabinet of Sri Lanka formulated by Ranil Wickremesinghe government that came into power in August 2015 elections of Sri Lanka.

The ministry was in charge of discovering solutions to resolve the garbage, housing of shanty dwellers issues as well drawing new traffic plans to avoid traffic jams in busy towns.

[1][2] The state institutions came under the purview of the ministry were National Physical Planning Department, Urban Development Authority and Sri Lanka Land Reclamation and Development Corporation.

[3] The ministry was trying to establish a Megapolis Authority under a parliamentary act, to plan the development activities of the Western Province.

On 21 November 2019, The Ministry of Megapolis and Western Development was dissolved and the institutions came under it was assigned to newly formed "Ministry of Urban Development, Water Supply and Housing Facilities" which is governed by Prime Minister Mahinda Rajapakse Sri Lanka Freedom Party Jathika Hela Urumaya