Present disclosure relates to a one-way airflow valve and electronic cigarettes having the one-way airflow valve. In certain embodiments, the electronic cigarette includes: a mouthpiece assembly, an E-liquid storage tank for storing E-liquid, a vaporizer assembly having a one-way airflow valve, an electric power connector for receiving electric power, and a condensed E-liquid vapor collection slot for collecting condensed E-liquid vapor to be reused. The mouthpiece assembly and vaporizer assembly form an airflow path. When user connects electric power source to the electric power connector, and sucks electronic cigarette through a mouthpiece, air pressure inside electronic cigarette is reduced which creates air pressure difference, such air pressure difference pushes a one-way airflow blocker upwards to open airflow path, and when user stops sucking, one-way airflow blocker returns to a first position under resilient force of the one-way airflow valve spring to close the airflow path.
