Helsinki University of Technology (TKK; Finnish: Teknillinen korkeakoulu; Swedish: Tekniska högskolan, HUT in international usage) was a technical university in Finland. It was located in Otaniemi, Espoo in the Helsinki metropolitan area, and it was one of the three universities from which the modern day Aalto University was founded. The university was founded in 1849 by Grand Duke of Finland, Emperor Nicholas I and received university status in 1908. It moved from Helsinki to Otaniemi campus area in 1966. The merger of HUT with two other schools created the Aalto University in 2010, and HUT briefly held the name Aalto University School of Science and Technology before being split into four schools in 2011.

Much of the university's Otaniemi campus was designed by Alvar Aalto.

In 1849, TKK was established in Helsinki by the decree of the Russian Emperor Nicholas I, Grand Duke of Finland as a "manufacture and handicraft school", with the name Helsingin teknillinen reaalikoulu/Helsingfors tekniska realskola, along with two other similar schools, situated in Vaasa and Turku. The school started its function in the Domus Litonii ("Litonius house") building located at Aleksanterinkatu 50, which had been designed by Gustaf Paulus Leander and completed in 1847, and remains in use and in ownership by the Litonius family to this day.

In 1872, the school's name was changed to Polyteknillinen koulu/Polytekniska skolan ("Polytechnical School") and in 1878, to Polyteknillinen opisto/Polytekniska institutet ("Polytechnical Institute"), while the two other manufacture and handiwork schools were demoted to institutions of lower level. In 1877 the school moved to larger premises to a new building near the Hietalahdentori market square. As the proportion of matriculation diploma holders in the student intake gradually increased, the school gained more social respectability. In 1908, TKK was given university status along with its present name, thus becoming the second university to be founded in Finland. In 1955, building of the new campus area started with the housing village. In 1966, TKK moved from Helsinki to the new campus in Otaniemi, Espoo.

In the past, the university was also known by the abbreviations HUT and TH, from its English- and Swedish-language names, but in 2005 a decision was made officially to use the abbreviation TKK exclusively, for branding reasons.

In 2010, TKK was merged with Helsinki School of Economics and University of Art and Design Helsinki into Aalto University. After brief existence in the new university as own institution, Aalto University School of Science and Technology, it was split into four schools, corresponding to four old faculties, School of Engineering, School of Science, School of Electrical Engineering, and Aalto University School of Chemical Technology. In 2012, the Department of Architecture of the School of Engineering, formerly of Faculty of Engineering and Architecture, was merged with Aalto University School of Art and Design into Aalto University School of Arts, Design and Architecture.

All engineering programmes offered by TKK led to the degree of diplomi-insinööri ("engineer with university diploma"), a five-year master's degree. The only exceptions to this were the architecture programmes that lead to the master's degrees of architecture and landscape architecture. From 2005, according to the Bologna process, all students might also complete an intermediate degree (tekniikan kandidaatti, TkK) before the DI or architect's degree. This degree is considered a bachelor's degree and enables enrollment in foreign universities where a bachelor's degree is required. TKK did not offer programs terminating in a bachelor's degree; a student might only be accepted to study for the Master's level degree. TKK required a bachelor's degree from foreign students studying in English, because only Master's studies were offered completely in English.

Apart from numerous programs in Finnish, various international Masters programs were offered exclusively for studies in English.