Abstrak Kemampuan serta perkembangan manusia di bidang teknologi bergerak begitu cepat, seiring berjalanya waktu dari abad ke abad. Berbagai macam teknologi yang manusia ciptakan untuk kepentingan individu maupun kelompok yang memiliki fungsi dan tujuan yang berbagai macam. Salah satunya yaitu Alat Monitoring Kinerja Pompa Dosing PAC Berbasis IoT(Internet of things). Alat monitoring ini tentunya sangat membantu dalam memudahkan operator produksi di instalasi pengolahan air. Tujuannya adalah memonitoring kinerja pompa dan proses koagulasi. Pada saat cairan pac dan air baku melakukan proses pembubuhan pada bak koagulasi yang ada di setiap gedung instalasi, yang nantinya akan menentukan dari hasil air baku yang di olah. Oleh sebab itu, penulis membuat Alat Monitoring Kinerja Pompa Dosing PAC Berbasis IoT(Internet of things), yang akan terhubung ke modul elektronik lainya seperti, colokan adaptor, nodemcu esp8266, modul step down, sensor relay, pompa air mini, sensor hujan, aplikasi blynk, dan device hp samsung A3 2016. Langkah selanjutnya adalah memprogram setiap komponen agar terkoneksi satu sama lainya, oleh nodemcu sebagai basis dari proses yang akan menghasilkan inputan berupa notifikasi kepada user berupa notifikasi pada device. Kata Kunci: Internet Of Thing, Nodemcu, Sensor Relay, Pompa Air, Sensor hujan, Blynk. Abstract Capabilities and development in the field of technology move so fast, over time from century to century. Various kinds of technology that humans have created for the benefit of individuals and groups that have various functions and purposes. One of them is an IOT (Internet of things) based Dosing pump performance monitoring tool. This monitoring tool is of course very helpful in facilitating production operators in water treatment installations. Its purpose is to monitor pump performance and the coagulation process. When the pac liquid and raw water carry out the affixing process in the coagulant tanks in each installation building, which will later determine the results of the processed raw water. Therefore, the author created an IOT (Internet of things) Based Pac Dosing Pump Performance Monitoring Tool, which will be connected to other electronic modules such as adapter plugs, nodemcu esp8266, step down modules, relay sensors, mini water pumps, rain sensors, applications blynk, and the Samsung A3 2016 cellphone device. The next step is to program each component so that it is connected to each other, by nodemcu as the basis of the process which will produce input in the form of notifications to the user in the form of notifications on the device. Keywords: Internet Of Thing, Nodemcu, Sensor Relay, Water Pump, Rain Sensor, Blynk.