Igahlo, 29, finished as the leading scorer in the 2019 Africa Cup of Nations Qualifying rounds and terrorised defences in the Chinese top-flight last season with 21 goals in 28 games.
Despite finishing as the second highest scorer in the division, his Changchun Yatai side suffered relegation and the Super Eagles striker was subsequently linked with a return to the Premier League and LaLiga.
Having featured in both countries with Watford and Granada respectively, the prolific forward has revealed he was approached by the Blaugrana in the last transfer window before they turned to Kevin Prince Boateng.
"My agent spoke to me about a loan interest from Barcelona. The club wanted a striker with La Liga experience and someone who understands Spanish football," Ighalo told BBC Sport.
"It was meant to be a six-month loan and strictly as a back-up striker. It was nice to hear that Barcelona were interested and any footballer would be more than happy to take it.
"But with due respect I had just finished as the second top scorer in China with 21 goals, I deserve better and didn't want to be a short-term player somewhere.
"We rejected it, it was an easy decision to make and I chose to stay in China by joining Shanghai Shenhua on a longer contract."
Ighalo added: "You need to weigh things up properly in life and ask yourself if it is your call to make, or one to satisfy others.
"I respect my decision. I needed to focus on what is good for my career long-term and when you decide to do something - you stay true to yourself. It wasn't for me and I am happy where I am."
The Nigeria international has scored two goals in his opening three starts in the new Chinese top-flight season.