The China-based attacker is on the verge of sealing a sensational return to English football as talks between the two sides have been productive.
According to the insider, the Ghana ace will undergo the medical Monday before sealing the loan switch from Shanghai SIPG.
The 30-year-old arrived in England on Sunday morning and opened talks with the Royals over a loan switch.
The powerful striker is considering the season-long loan move away Shanghai SIPG who have exhausted their foreign players' quota.
If Gyan passes his medical, his signing will prove to be a massive coup for Reading thanks to his high profile and showmanship.
Gyan is being lined up by the Royals as a replacement for injured striker Deniss Rakels.
Signing the deal will seal his return to England after spending two years with Sunderland before leaving for UAE side Al Ain in 2012.
Gyan joined Sunderland from French side Rennes in 2010.
He was a major hit at Al Ain where he scored a staggering 73 goals in 65 games with 44 goals coming in one season.
Gyan is also record scorer for Ghana as he has scored 48 goals from 95 appearances for the Black Stars.