The 32-year-old, who was top scorer in La Liga four years ago for Real Mallorca before going on to help Spain win Euro 2008, arrived in Malaysia on Sunday ahead of his proposed move, local media reported.
The Getafe forward said he had offers from other clubs in Europe but was keen to move to Malaysia despite his lack of knowledge about the league.
"To be honest I don't know much about Malaysian football, but I watched videos of the local matches on the internet before coming down here and what I observed was Malaysians appear very passionate about their football," Guiza told local media.
"I'm really happy to come here as this will be a new and great experience for me."
After his standout season in 2008, Guiza joined Turkish side Fenerbahce for 14 million euros before returning to Spain last year and signing a three-year deal with Getafe.
But Guiza has hardly featured of late in his second spell with the club leading to him looking for a new challenge.
"I want to help Johor become not only the top team in Malaysia but in Asia as well," said Guiza, who has scored six goals in 21 internationals.
Ambitious plans and a number of new signings have led Johor, who finished ninth in the 14-team Super League this season, to be dubbed the "Manchester City of Malaysia" by local media after the big spending English champions.
Johor FA president Tunku Mahkota Johor Tunku Ismail Sultan Ibrahim said last month he wanted to bring in two high-profile foreign signings to improve the fortunes of the club, who last won the league title in 1991.
"I would be glad and honoured to have a player of such calibre join us. The issue isn't the money offered to him but whether he can settle here quickly," Tunku Ismail said of Guiza.
"Hopefully, we will be able to strike a deal as soon as possible so I can take him around and show him what Johor has to offer."
Johor must register their squad for the 2013 Malaysia Super League season by December 13.
