The 2016–17 Treća HNL season is the 26th since its establishment.
The league consists of three regional groups, Istok (East), Jug (South) and Zapad (West).
50 teams will join the league, including two relegated from the 2015–16 Druga HNL and five promoted from the lower leagues.
| Competition: | Treća HNL East |
| Season: | 2016–17 |
| League Topscorer: | 11 goals Josip Špoljarić (Osijek II) Nenad Erić (Međimurje) Ivan Jakešević (Slavonija) |
| Biggest Home Win: | Varaždin 6−1 Bjelovar Vukovar '91 5−0 Slavonija Belišće 5−0 Đakovo Croatia |
| Biggest Away Win: | Đakovo Croatia 1−5 Osijek II |
| Highest Scoring: | Varaždin 6−1 Bjelovar Višnjevac 2−5 Osijek II |
| Matches: | 144 |
| Total Goals: | 347 |
| Updated: | 22 March 2017 |
| Team | Home city | Stadium | Capacity | |
|---|---|---|---|---|
| Bedem Ivankovo | Ivankovo | Grac | 1,000 | |
| Belišće | Belišće | Gradski stadion | 5,000 | |
| Bjelovar | Gradski stadion | 4,000 | ||
| BSK | Bijelo Brdo | Igralište BSK-a | 1,000 | |
| Đakovo | Stadion na Pazarištu | 3,000 | ||
| Koprivnica | Gradski stadion | 3,500 | ||
| Marsonia | Slavonski Brod | Stadion uz Savu | 8,000 | |
| Međimurje | Čakovec | SRC Mladost | 6,000 | |
| Mladost Ždralovi | Ždralovi | Igralište NK Mladosti | 1,000 | |
| Oriovac | Igralište NK Oriolika | 1,500 | ||
| Osijek | Igralište u Donjem gradu | 1,000 | ||
| Pleternica | Stadion Stjepan Zdenko Šivo | 700 | ||
| Slavonija | Požega | Stadion kraj Orljave | 4,000 | |
| Varaždin | Varaždin | Stadion Anđelko Herjavec | 9,099 | |
| Višnjevac | Višnjevac | Stadion NK Višnjevca | 1,500 | |
| Vukovar '91 | Vukovar | Gradski stadion | 6,000 |
| Competition: | Treća HNL South |
| Season: | 2016–17 |
| League Topscorer: | 12 goals Vlatko Blažević(Zadar) |
| Biggest Home Win: | Hajduk II 8−0 Val |
| Biggest Away Win: | Jadran LP 0−5 OŠK Otok |
| Highest Scoring: | Hajduk II 8−0 Val |
| Matches: | 153 |
| Total Goals: | 425 |
| Updated: | 29 November 2016 |
| Team | Home city | Stadium | Capacity | |
|---|---|---|---|---|
| BŠK Zmaj | Blato | Zlinje | 3,000 | |
| Zmijavci | ŠRC Marijan Šuto Mrma | 1,000 | ||
| GOŠK Dubrovnik 1919 | Dubrovnik | Lapad | 3,000 | |
| Hajduk II | Split | Poljud | 34,448 | |
| Hrvace | Hrvace | Gradski stadion | 3,075 | |
| Jadran LP | Ploče | Igralište NK Jadrana | 2,000 | |
| Junak | Sinj | Gradski stadion | 3,096 | |
| Kamen Ivanbegovina | Ivanbegovina | Igralište NK Kamena | 1,000 | |
| Neretva | Metković | Igralište iza Vage | 2,000 | |
| Opuzen | Podvornica | 2,500 | ||
| Omiš | Omiš | Stadion Anđelko Marušić-Ferata | 5,000 | |
| Orkan | Dugi Rat | ŠRC Dalmacija | 3,000 | |
| OŠK Otok | Otok | Igralište NK Otok | 450 | |
| Primorac B/M | Biograd na Moru | Gradski stadion Kazimir i Silvio | 1,500 | |
| Primorac 1929 | Stobreč | Igralište u Blatu | 3,600 | |
| Val | Kaštel Stari | Vukovar | 2,000 | |
| Zadar | Zadar | Stanovi | 5,860 | |
| Zmaj Makarska | Makarska | Gradski sportski centar | 5,000 |
| Competition: | Treća HNL West |
| Season: | 2016–17 |
| Winners: | NK Vinogradar |
| Promoted: | NK Kustošija |
| League Topscorer: | 10 goals Goran Ljubojević (Vinogradar) |
| Biggest Home Win: | Krk 4−0 Segesta Maksimir 5−1 Zagorec Vrapče 5-1 Opatija |
| Biggest Away Win: | Jadran Poreč 0−5 Vinogradar |
| Highest Scoring: | Kustošija 4−3 Opatija |
| Matches: | 120 |
| Total Goals: | 334 |
| Updated: | 5 June 2017 |
| Team | Home city | Stadium | Capacity | |
|---|---|---|---|---|
| Dubrava | Zagreb | ŠRC Grana-Klaka | 2,000 | |
| Dugo Selo | Gradski stadion | 2,000 | ||
| HAŠK | Zagreb | ŠRC Pešćenica | 3,000 | |
| Jadran Poreč | Poreč | Veli Jože | 2,000 | |
| Krk | Krk | SRC Josip Uravić Pepi | 500 | |
| Kustošija | Zagreb | Igralište Kustošije | 2,550 | |
| Maksimir | Zagreb | Oboj | 247 | |
| Opatija | Opatija | Stadion NK Opatije | 2,000 | |
| Samobor | Samobor | SC NK Samobor | 5,000 | |
| Segesta | Sisak | Gradski stadion | 8,000 | |
| Gornji Stupnik | SRC Stupnik | 1,000 | ||
| Trnje | Zagreb | Stadion Trnja | 1,000 | |
| Vinogradar | Jastrebarsko | Mladina | 2,000 | |
| Vrapče | Zagreb | Igralište Vrapča | 1,000 | |
| Vrbovec | Vrbovec | Gradski stadion kraj Sajmišta | 4,000 | |
| Zagorec | Krapina | ŠRC Podgora | 2,000 |