Hamedan province with an area of 19496 km2 is bounded on the north by Zanjan and Ghazvin  province, on the south by lorestan province, on the east by markazi province, and on the west by kermanshah and kordestan province. It is situated between northern latitude of 33o  59’ to 35o  48’ and eastern longitude of 47o  34’ and 49o 36’. According to the latest administrational divisions of the country ( census of 1996), it consists of eight townships ( hamedan, malayer, Tuyserkan, Nahavand, Asad Abad, Kabodarahang, Bahar, Razan, Lalejin, Maryanaj, Famenin, Saleh Abad, Ghorveh Darjazin, Serkan, Firozan, Azandarian, Damagh, Farasfaj, Ghahavand and joraghan); 21 counties:

Markazi, Shara, Famenin, ( in hamedan); Markazi, Jokar, Samen ( in Malayer); Markazi, khezel ( in Nahavand); Markazi , Gholgholrood (in Tuyserkan); Markazi (in Asad Abad); Markazi, Goltappeh, Shirinsu ( in Kabudarahang); Markazi, Ghorve Darjazin, sardrood    ( in Razan); and Markazi, Saleh Abad, Lalejin ( in Bahar). In addition, there are 71 rural districts and 1120 villages. The population of the province, according to the census of the 1996 is 1677957, 810640 of them are living in urban districts and another 867115 of them in rural districts. The relative density of the population was about 68 per sq.km in the same year. There are different tribes and dialects in the province and most of them speak Persian , but some of them also speak Lori, Turkish, and Kordish, because of their adjacency to Zanjan, GHazvin, Lorestan, Kermanshah, and Kordestan.

Main Heights
Alvand peak with an altitude of 3574 meters is the highest peak in the province. It is natural boundary between Hemadan and Tuyserkan.
Mount Garo in the south of the nahavand (3316), Mount Lashgardar  in the southwest of the malayer (2928), Mount khangormaz in the west of the Tuyserkan (2868), Mount siahdarreh in Tuyserkan (2818), Mount Sefid in the southwest of Malayer, Mount Almabolagh between Asad Abad and Bahar, Mount Bughati in Kabodarahang are among the other heights. The lowest part of the province with an altitude of 1420 meters, is the place the Gamasyab River flows out of Nahavand Township.

Province Climate
Various heights, plains, mountainous regions, high peaks, rivers, springs, lands, trees and headwaters cause Hamedan climate to be changeable. Usually, winter  are cold and snowy and summers are mild. It is cold in the northern parts of the province and slopes of mount Alvand, but in the southern parts it is mild.

Main Rivers
Gamasab (Gamasyab) River: It is one of the longest rivers throughout the country. It originates from Gamasab Headwater in the southwest of Nahavand and irrigates surrounding  lands. Malayer Khormabad River in leily Yadagar village and Tuyserkan Gholgholrood River in Gardian village empty into it. Gamasab is the one of the main branches of karkhe River  that empties in Persian Gulf.
Ghogholroor River: Its headwater is southern parts of Mount Alvand and it consists of Sarabi River ( from kolahghazi peak), Serkanrood River ( from serkan heights), karzanrood River ( from Geshani and Sanjuzeh valleys). After irrigating Tuyserkan land, its empties into Gamasab River.
Gharahchay (Ghurichai) River: It originates from Zaghe pass  Heights and Alfavot valley between Hamedan and Malayer. After passing through Amzagerd, it empties into Gharahchay River with other springs like: Khaku, Darreh Morad Beik, Vafragin, Siminehrood, and Hamehkasi.
After irrigating famenin and Ghahavand lands, its flows up the Markazi province and empties into Ghom Lake.
Khoramrood River: It originates from northern valley of Shahrestane village. ( It is located southwest of Mount Alvand and northwest of Tuyserkan). After irrigating land, it leaves Tuyserkan.
Talvar River: It originates from  Mount  Sefid,  it is also one of the headwater of Ghezel Ozan River that is called Sefidrood River in Gilan province and empties into Caspian Sea. Its length in Hamedan province is not noticeable.