The Lexus LF line is a series of concept cars built by Lexus, the luxury vehicle division of Toyota Motor Corporation. The "LF" designation refers to Lexus Future.^{[citation needed]} The LF Series vehicles features coupes/convertibles, including: the LF-A, the LF-A Roadster, LF-LC, LF-CC, and the LF-C; sedans: the LF-S, LF-Sh, and LF-Gh; crossover SUVs: the LF-X and LF-Xh; and hatchbacks: the LF-Ch. The first concept vehicle of the LF Series, the LF-X, appeared in 2003. The LF Series utilizes L-finesse, a design philosophy named for "Leading Edge" and "finesse", which debuted on the LF Series concepts and later extended to all new production Lexus vehicles. New vehicle technologies on the LF Series include advanced instrumentation, multiple driver-selected vehicle configurations, hybrid and experimental powertrains, and unconventional driver interface designs. The vehicles also feature new design cues which derive from the L-finesse design language of "Intriguing Elegance" (純), "Incisive Simplicity" (妙), and "Seamless Anticipation" (予). Several of the LF concept vehicles have appeared close to their production counterparts, while the design cues of other LF concepts appeared on more distinctly different production vehicles.

The LF-A is a 2-door exotic concept car built as a prospective halo car for the Lexus division. Three versions have been shown, the first of which debuted at the 2005 North American International Auto Show (NAIAS). The designation stands for Lexus Future-Advance. The first concept was about five inches shorter than the Porsche 911 Turbo (996) with a wheelbase about nine inches longer, and was nearly 48 inches (1,200 mm) in height about equal to the Ferrari F430 with a width of 73.2 in (1,859 mm). It was powered by a V10 engine displacing 4.8 liters, generating over 550 hp (410 kW) and had a top speed around 208 mph (335 km/h). To maintain a near ideal weight distribution a rear transaxle is used and the radiators are mounted at the rear. A second revised version with a more completely furnished interior and exterior was unveiled two years later at the 2007 NAIAS as a possible future member of the Lexus F marque performance lineup. The interior gauges revealed a 9,000 RPM redline, however news reports speculated that it might not make the production version. The third version of the LF-A concept, a roadster model, premiered in 2008.

Reports in 2006 indicated that the LF-A concept car had received the green-light for production. Prototypes of the LF-A had been spotted regularly undergoing testing at Nürburgring since October 2004, the famous motorsport race track in Nürburg, Germany. Numerous test vehicles have been equipped with automatic retractable rear wings, and carbon ceramic brake discs. The production vehicles were expected to carry V10 engines, putting the car in market competition with the Lamborghini Gallardo, Ferrari F430, the Porsche 911 (997), and the Chevrolet Corvette C6 ZR1. Pricing was estimated at over $225,000, and close to $400,000. In December 2007, Auto Express reported that the LF-A had set an unofficial 7:24 lap record at the Nürburgring. The production $375,000 Lexus LFA supercar debuted in 2009.

Designated LF-AR or LF-A Roadster, the roadster version of the LF-A concept car was first displayed at the North American International Auto Show in Detroit on January 13, 2008. Derived from the LF-A, the designation stands for Lexus Future-Advance Roadster. Initial specifications for the roadster are a V10 engine under 5.0 L with over 500 hp (373 kW) and a top speed of over 200 mph (320 km/h). The LF-A Roadster was also revealed to have a retractable rear spoiler for improved handling at speed. The LF-A Roadster show model featured side cameras in place of standard mirrors, and a two-tone interior. The model was designated with "F" badges indicating its place as a member of the Lexus F performance division.

After its debut at the 2008 North American International Auto Show, the LF-A Roadster was also shown at the 2008 Pebble Beach Concours d'Elegance, the 2008 Geneva Motor Show, the United States Open Championship tournament, and at Lexus exhibits in Japan. On August 12, 2009, news reports suggested that the LF-A would be released as the LF-L, with the change in name from A to L to signify its appearances at Le Mans and to draw on its pre-production racing development. However, a production non-convertible designated LFA premiered in October 2009.

The LF-C is a concept car Lexus unveiled at the 2004 New York Auto Show. This concept featured a retractable hardtop design which allowed for coupe, convertible, targa, or speedster configurations via a four-position glass roof. The designation stands for Lexus Future-Coupe. The LF-C is fitted with a V8 engine and rear-wheel drive. Unique features included a one-touch activation button, crystal LED taillamps, suede bucket seats, a 3D instrument panel, drive-by-wire, and a translucent crystal center console with blue backlighting. The LF-C also featured retractable rear-view cameras in place of side mirrors on the doors and rear bumper.

The design choices shown in the LF-C hinted at a convertible version of the IS 250/350. Design cues from the LF-C, particularly in the front fascia, appeared in production form with the debut of the second generation Lexus IS. The LF-C concept measured 178.7 in (4,539.0 mm) long, 73.0 in (1,850 mm) wide, and 53.5 in (1,358.9 mm) in height, with a wheelbase of 110.0 in (2,790 mm).

The LF-C2 is a concept car Lexus unveiled at the 2014 Los Angeles Auto Show.^{[citation needed]}