Nyangweso first ran for an elective office in 2016 when he contested for Samia-Bugwe South seat in the parliament but lost to incumbent Julius Maganda Wandera. Following the creation of Samia-Bugwe Central constituency, he ran for the ticket of National Resistance Movement polling 8,849 votes but lost by a wide margin to Richard Wanyama Hamala who received 14,423 votes. Nyangweso went into the 2021 election as an independent candidate and won with 13,919 votes to beat Richard Wanyama of NRM who polled 11,312 votes. Nyangweso is the pioneer MP to occupy Samia-Bugwe Central seat in the 11th parliament.