The change of government that took place after the GE 14 demanded a review to be carried out on the pattern of agenda setting among the news media in this country, especially on social media. Therefore, this study examines how the mainstream media, alternative media and government media set their issue’s salience agenda on Twitter during the pre and post GE 14. A total of 7,533 tweets from six media organisations namely Berita Harian, The Star, Malaysiakini, Free Malaysia Today, BERNAMA and RTM were downloaded and analysed. A content analysis, bivariate correlation analysis and time-lagged analysis were conducted to identify the hierarchical pattern of issue’s salience and the causal relationship between issue’s salience agendas between these media. From the analysis, it was found that the mainstream media, the alternative media and the government media have a different inclinations in setting up their most important issue on Twitter during the pre and post GE 14. Mainstream media were found to place sports issues as the most important issue on their agenda on Twitter, while for alternative and government media, political issues and issues of national administration and governance were their top priorities. Meanwhile, the transition of the government post GE 14 also has an impact on the causal relationship between agendas involving the mainstream media, the alternative media and the government media on Twitter. For instance, during the pre GE 14 period, the agenda of the mainstream media did not have a significant relationship with the agenda of the government media. However during the post GE 14 period, the agenda of the two media was found to have a significant relationship. In the context of the causal relationship, the two media did not have a mutual influence on each other during the pre GE 14 period, but this situation changed after the GE 14. As for the alternative media, its relationship with the government media also changed after GE 14 in which its agenda no longer influences the government’s media agenda and vice versa. During the pre GE 14 period, the two media were found to have mutually influenced each other in their agenda on Twitter. Perubahan tampuk pemerintahan yang berlaku selepas Pilihan Raya Umum ke-14 (PRU 14) menuntut agar penelitian semula dilakukan terhadap corak penentuan agenda dalam kalangan media berita di negara ini terutamanya di laman sosial. Sehubungan itu, kajian ini meneliti bagaimana media arus perdana, media alternatif dan media kerajaan mengetengahkan agenda penonjolan isu mereka di laman Twitter semasa tempoh pra dan pasca PRU 14. Sebanyak 7,533 ciapan daripada enam organisasi media yang terdiri daripada Berita Harian, The Star, Malaysiakini, Free Malaysia Today (FMT), BERNAMA dan RTM telah dimuat turun dan dianalisis. Analisis kandungan, analisis korelasi bivariat dan analisis sisih masa telah dijalankan untuk mengenalpasti corak hierarki penonjolan isu dan hubungan kausaliti agenda penonjolan isu antara media-media ini. Hasil analisis yang dijalankan mendapati bahawa media arus perdana, media alternatif dan media kerajaan mempunyai kecenderungan yang berlainan dalam menentukan isu terpenting bagi mereka di laman Twitter semasa tempoh pra dan pasca PRU 14. Media arus perdana didapati meletakkan isu sukan sebagai isu terpenting dalam agenda mereka di laman Twitter, manakala bagi media alternatif dan media kerajaan pula, isu politik dan isu pentadbiran negara dan pemerintahan menjadi keutamaan mereka. Sementara itu, peralihan kerajaan pasca PRU 14 juga turut memberi impak terhadap hubungan kausaliti antara agenda yang melibatkan media arus perdana, media alternatif dan media kerajaan di laman Twitter. Misalnya semasa tempoh pra PRU 14, agenda media arus perdana tidak mempunyai hubungan yang signifkan dengan agenda media kerajaan. Namun semasa pasca PRU 14, agenda kedua-dua media tersebut didapati mempunyai hubungan yang signifikan. Dalam konteks hubungan kausaliti pula, kedua-dua media tersebut tidak mempunyai hubungan saling mempengaruhi antara satu sama lain semasa tempoh pra PRU 14 namun keadaan ini berubah selepas PRU 14. Bagi media alternatif pula, hubungan media tersebut dengan media kerajaan juga turut berubah pasca PRU 14 yang mana agenda media tersebut tidak lagi mempengaruhi agenda media kerajaan dan begitu juga sebaliknya. Semasa tempoh pra PRU 14, kedua-dua media tersebut didapati mempunyai hubungan saling mempengaruhi antara satu sama lain dalam penentuan agenda di laman Twitter.