Characteristics and operational regimes of electron density, electron temperature, and energy confinement have been investigated in the JT-60SA first plasma operation phase. Working gases for these plasma discharges are hydrogen (H2) and helium (He). A plasma current of 1.2 MA has been achieved at a toroidal magnetic field of 2 T. In 1 MA, the operational regimes of a line-averaged electron density are – m for the He-gas injected plasma and – m for the H2-gas injected plasma. A maximum electron temperature in this operation phase is 2.0 keV in the core region in the case of He-gas-injection and 1.13 MW electron cyclotron resonant heating. A global energy confinement time of L-mode divertor plasmas for both the He-gas-injected and H2-gas-injected plasmas strongly depends on the total input power. In the similar total input power regimes, increases with an increase in , leading to the possibility of these plasmas in the linear ohmic confinement regime. The global energy confinement time of the H2-gas-injected plasmas, which is in the range of 100–200 ms, is compared with the ITER89-P scaling law, resulting in being 0.6 to 1.2 times the scaling, mostly around or slightly below it. The dependence of on matches the neo-Alcator scaling law and reaches the ITER89-P scaling law in higher-density plasma in the case of the similar total input power regimes.