In July 1968 Mazda added a Familia Rotary model to the range, offered in both two-door coupé and four-door sedan variants.
Sedan models were given an additional "SS" nameplate.
The Familia Rotary was powered by a 982 cc 10A rotary engine and the coupé version was sold outside Japan as the "Mazda R100".
After an April 1970 update (known colloquially in Australia as the Series 2) it was known as the "Familia Presto Rotary" in Japan as the Presto nameplate was added into the entire Familia range.
Power was rated at just 100 PS (74 kW) due to a small carburetor (thus the "R100" name).
The rotary engined R100 has a unique front end design, with a more prominent pointed hood, grille, and bumper.
The rear also gained its own design with twin round tail lights, which became for a time a signature design element for the rotary engined versions of Mazda's cars.
Inside, the cars were more sumptuously appointed with plusher seats and chrome plated accents, full sized interior door trim panels, a floor mounted handbrake lever, and a unique cockpit styled dashboard with full instrumentation.
Mazda referred to this dashboard as the "T-Dash", and fitted it to top spec piston engined variants of the Familia on the Japanese market as well as the rotary models.

In Japan, the installation of a rotary engine gave Japanese buyers a financial advantage when it came time to pay the annual road tax in that they bought a car that was more powerful than a traditional inline engine, but without having the penalty for having an engine in the higher 1.0-litre tax bracket.
This was the only generation of the Familia that had the rotary engine offered.
When Mazda updated the rotary engine to single distributor design in late 1973 with a raft of improvements to improve reliability and fuel economy, the smaller 10A engine was discontinued.
Upgrading the Familia Rotary to the 12A engine would have cost the car its tax advantage in Japan, and the decision to discontinue it was made, despite the Familia body continuing production for some years to follow.

The R100 was one of the first Mazda cars imported into the United States for the new Mazda Motors of America, sold in model years 1971 and 1972.
Due to US regulations it was released in North America with round headlights fitted in place of the rectangular lights fitted in all other markets.
It was a surprising hit with the American public, though sales were limited to some Northwestern states initially.

Following on the success of the Cosmo Sports at Nürburgring in 1968, Mazda decided to race another rotary car.
The Familia Rotary coupé won its first outing, at the Grand Prix of Singapore, in April 1969.
Next, the company took on the touring car endurance challenge at Spa, the Spa 24 Hours.
For 1969, Mazda entered a pair of Familia Rotary coupés.
The cars came fifth and sixth the first year after a quartet of Porsche 911s.
The Familia also placed fifth at the Marathon de la Route at Nürburgring in 1969, the same race that the Cosmo had bowed at the previous year.
Finally, Mazda took the Familia home for the Suzuka All-Japan Grand Cup, where it won easily.
For 1970, the Familia placed eighth at the RAC Tourist Trophy in June, followed by a fourth place at the West German Touring Car race in July.
At Spa, four Familias were present, battling with BMW Alpinas, and Alfa Romeos for the podium.
This time, three of the Mazdas retired, with the fourth claiming the fifth position.
Mazda also turned its attention to Le Mans in 1970 with rotary-powered prototypes.
The company finally won that race 21 years later with the 787B.
In July 1968 Mazda added a Familia Rotary model to the range, offered in both two-door coupé and four-door sedan variants. Sedan models were given an additional "SS" nameplate. The Familia Rotary was powered by a 982 cc 10A rotary engine and the coupé version was sold outside Japan as the "Mazda R100". After an April 1970 update (known colloquially in Australia as the Series 2) it was known as the "Familia Presto Rotary" in Japan as the Presto nameplate was added into the entire Familia range. Power was rated at just 100 PS (74 kW) due to a small carburetor (thus the "R100" name). The rotary engined R100 has a unique front end design, with a more prominent pointed hood, grille, and bumper. The rear also gained its own design with twin round tail lights, which became for a time a signature design element for the rotary engined versions of Mazda's cars. Inside, the cars were more sumptuously appointed with plusher seats and chrome plated accents, full sized interior door trim panels, a floor mounted handbrake lever, and a unique cockpit styled dashboard with full instrumentation. Mazda referred to this dashboard as the "T-Dash", and fitted it to top spec piston engined variants of the Familia on the Japanese market as well as the rotary models.
In Japan, the installation of a rotary engine gave Japanese buyers a financial advantage when it came time to pay the annual road tax in that they bought a car that was more powerful than a traditional inline engine, but without having the penalty for having an engine in the higher 1.0-litre tax bracket. This was the only generation of the Familia that had the rotary engine offered. When Mazda updated the rotary engine to single distributor design in late 1973 with a raft of improvements to improve reliability and fuel economy, the smaller 10A engine was discontinued. Upgrading the Familia Rotary to the 12A engine would have cost the car its tax advantage in Japan, and the decision to discontinue it was made, despite the Familia body continuing production for some years to follow.
The R100 was one of the first Mazda cars imported into the United States for the new Mazda Motors of America, sold in model years 1971 and 1972. Due to US regulations it was released in North America with round headlights fitted in place of the rectangular lights fitted in all other markets. It was a surprising hit with the American public, though sales were limited to some Northwestern states initially.
Following on the success of the Cosmo Sports at Nürburgring in 1968, Mazda decided to race another rotary car. The Familia Rotary coupé won its first outing, at the Grand Prix of Singapore, in April 1969. Next, the company took on the touring car endurance challenge at Spa, the Spa 24 Hours. For 1969, Mazda entered a pair of Familia Rotary coupés. The cars came fifth and sixth the first year after a quartet of Porsche 911s. The Familia also placed fifth at the Marathon de la Route at Nürburgring in 1969, the same race that the Cosmo had bowed at the previous year. Finally, Mazda took the Familia home for the Suzuka All-Japan Grand Cup, where it won easily. For 1970, the Familia placed eighth at the RAC Tourist Trophy in June, followed by a fourth place at the West German Touring Car race in July. At Spa, four Familias were present, battling with BMW Alpinas, and Alfa Romeos for the podium. This time, three of the Mazdas retired, with the fourth claiming the fifth position. Mazda also turned its attention to Le Mans in 1970 with rotary-powered prototypes. The company finally won that race 21 years later with the 787B.
Mazda Familia