| Native Name: | 麻生藩 |
| Conventional Long Name: | Asō Domain |
| Common Name: | Asō Domain |
| Subdivision: | Han |
| Status Text: | under Tokugawa shogunate Japan |
| Government Type: | Daimyō |
| Capital: | Asō jin'ya |
| Today: | part of Ibaraki Prefecture |
| Year Start: | 1604 |
| Year End: | 1871 |
| Era: | Edo period |
was a feudal domain under the Tokugawa shogunate of Edo period Japan, located in Hitachi Province (modern-day Ibaraki Prefecture), Japan. It was centered on Asō Jin'ya in what is now the city of Namegata, Ibaraki. It was ruled for all of its history by the Shinjō clan.
Shinjō Naoyori, a retainer of Toyotomi Hideyoshi and lord of Takatsuki Domain in Settsu Province sided with the losing western forces in the Battle of Sekigahara in 1601, and was deprived of his lands. However, in 1604, after pledging his fealty to Tokugawa Ieyasu, he was restored to a 33,000 koku holding spanning eight districts of Hitachi and Shimotsuke Provinces, centered at Asō.
His son, Shinjō Naosada, divided the domain by giving 3000 koku to his younger brother Naofusa. The 5th daimyō, Shinjō Naonori succeeded as an infant, and the domain continued to be run by his retired father, the 4th daimyō Shinjō Naotoki, who had established himself at a subsidiary 7000 koku holding in Kashima District. However, when Shinjō Naonori died at age 17 without an heir, the domain was suppressed by the Tokugawa shogunate. Shinjō Naotoki successfully petitioned the Shōgun for its restoration later the same year, but was given only 3000 koku of hatamoto lands to add to his existing 7000 koku.
During the Boshin War, the domain assisted in the suppression of the Mito Rebellion. The site of Asō Jin'ya is now occupied by Asō Elementary School, and the house of the karō of Asō Domain has been preserved as a museum.[1]
The domain had a population of 6043 people in 1389 households per a census in 1838.[2]
As with most domains in the han system, Asō Domain consisted of several discontinuous territories calculated to provide the assigned kokudaka, based on periodic cadastral surveys and projected agricultural yields.[3] [4]
| Name | Tenure | Courtesy title | Court Rank | kokudaka | |
| Shinjō clan (Tozama) 1604-1871 | |||||
| 1 | 1604–1612 | Suruga-no-kami (駿河守) | Lower 5th (従五位下) | 33,000 koku | |
| 2 | 1612–1618 | Echizen-no-kami (越前守) | Lower 5th (従五位下) | 30,000 koku | |
| 3 | 1618–1662 | Echizen-no-kami (越前守) | Lower 5th (従五位下) | 30,000 koku | |
| 4 | 1662–1674 | Oki-no-kami (隠岐守) | Lower 5th (従五位下) | 30,000 koku | |
| 5 | 1674–1676 | --none-- | --none-- | 23,000 koku | |
| 6 | 1676–1677 | Oki-no-kami (隠岐守) | Lower 5th (従五位下) | 10,000 koku | |
| 7 | 1677–1708 | Tonomo-no-kami (主殿頭) | Lower 5th (従五位下) | 10,000 koku | |
| 8 | 1708–1735 | Suruga-no-kami (駿河守) | Upper 5th (従五位上) | 10,000 koku | |
| 9 | 1735–1755 | Etchu-no-kami (越中守) | Lower 5th (従五位下) | 10,000 koku | |
| 10 | 1755–1772 | Echizen-no-kami (越前守) | Lower 5th (従五位下) | 10,000 koku | |
| 11 | 1772–1803 | Suruga-no-kami (駿河守) | Lower 5th (従五位下) | 10,000 koku | |
| 12 | 1803–1845 | Tonomo-no-kami (主殿頭) | Lower 5th (従五位下) | 10,000 koku | |
| 13 | 1845–1865 | Suruga-no-kami (駿河守) | Lower 5th (従五位下) | 10,000 koku | |
| 14 | 1866–1867 | --none-- | --none-- | 10,000 koku | |
| 15 | 1867–1871 | Shimotsuke-no-kami (下野守) | Lower 5th (従五位下) | 10,000 koku | |