The 49-year-old, who won the tournament in 1994, shot a six-under 64 for a one-shot lead at the Kennemer Golf and Country Club in Zandvoort.
Jimenez had two bogeys and eight birdies to give him hope of adding another Spanish name to the Dutch event's trophy; Seve Ballesteros and Jose Maria Olazabal are also previous winners.
"Seve's first win on the European Tour was here in 1976, and Jose Maria (Olazabal) also won here in 1989, so hopefully I can win here, too. That would be fantastic," Jimenez said.
"When the sun came out I started to play my best golf," Jimenez added. "Holing my wedge shot from 40 metres on the 16th was very nice, then the birdie on the last was a great way to finish. I'm very happy.
"It's a nice course and it's in great condition, so I enjoyed my day very much. It's maybe not playing as firm as it normally would, because of all the wet weather we've had. But hopefully we can get a bit more sun and it will dry out over the next few days."
Trailing Jiminez was a group of six players at five under, consisting of Robert Allenby, Gary Orr, Pablo Larrazabal, Damien McGrane, David Howell and Fabrizio Zanotti.
"Kennemer's special," Scotsman Orr said. "It's a real old-style golf course. You've got to put it in the right spots on the fairways and especially the greens. But I like the challenge, it's a pleasure to play courses like this."