Samuel, 24, who last played for Isreali club Beitar Jerusalem will be enjoying his second tint with a Chinese club after featuring for Guangzhou R&F from 2014 to 2017.
The former Dolphins striker mutually terminated his contract with Beitar Jerusalem last December and had been without a club ever since.
He scored 15 goals in 35 appearances for Guangzhou R&F during his stint at the club.
Samuel also once had stint with Russian clubs, CSKA Moscow and Amker Perm, as well as Norwegian teams; Valeranga and Sarpsborg.
Schifuan Longfor will hope Samuel can help them secure promotion to the Chinese Super League at the end of the season.
Odion Ighalo and Sone Aluko are the two Nigerian plying their trade in the CSL with Shanghai Shenhua and Beijing Renhe.
By Adeboye Amosu