The observation of the sky at millimetre wavelengths in the past years contributed to tremendous improvements in our understanding of a great variety of scientific topics ranging from the star formation in the Milky Way to the measurement of cosmological parameters. The advent of the NIKA2 camera at the IRAM 30-m telescope has opened a new route to reveal the details of the formation and evolution of structures throughout the Universe. This conference is dedicated to the scientific exploitation of the NIKA2 camera installed at the IRAM 30-m telescope (Pico Veleta, Spain) and opened to the scientific community. It will be organised by LPSC in June 3-7, 2019. This international conference will bring together the scientific community working on science done with NIKA2 observations. It includes both theoretical and observational topics related to the mm Universe, from stellar to cosmological scales. The mm Universe conference is funded by the ANR (French national agency for research) through the NIKA2Sky project. Financiel support from Focus labex is also acknowledged. This conference is dedicated to the scientific exploitation of the NIKA2 camera installed at the IRAM 30-m telescope (Pico Veleta, Spain) and opened to the scientific community. It will be organised by LPSC in June 3-7, 2019.