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Abstract Two-photon absorption (2 PA) with three-dimensional (3D) resolution and deep penetration of light into absorbing materials hold great promise for many applications such as 3D microscopy, 3D microfabrication, polymerization and optical data storage. We herein designed and synthesized two novel series of arylamine-coumarin based donor-acceptor dyads that showed good two-photon absorption activities. Tested by an open/close aperture Z-scan technique, the largest 2 PA cross-section value is 103.6 GM and the largest two-photon absorption coefficient (β) is 7.84 × 10−12 cm W−1. Fluorometric and electrochemical studies further reveal the formation of intramolecular charge transfer (ICT) among two dyads. Photoinduced singlet excited state intramolecular charge separation states were confirmed by ultrafast laser flash photolysis analyses coupled with TD-DFT excited state calculations. Surprisingly, the experimental measured lifetime of singlet excited state intramolecular charge separation state may be a diagnostic criterion for 2 PA cross-section of donor-acceptor systems. This work provides a new strategy for designing high-efficiency 2 PA materials. Graphical abstract Image 1 Highlights • Two novel series of arylamine-coumarin based donor-acceptor dyads have been designed and synthesized. • Both compounds showed good two-photon absorption activities. • The largest two-photon absorption coefficient (β) is 7.84 × 10−12 cm W−1 and the largest 2PA cross-section value is 103.6 GM. • Photoinduced singlet excited state intramolecular charge separation states were confirmed experimentally and theoretically. • The lifetime of singlet excited state intramolecular charge separation state may be a diagnostic criterion for 2PA. [ABSTRACT FROM AUTHOR]