A multimodal brain function signal acquisition device, comprising: a cap; an electroencephalogram signal acquisition device which comprises a support member and a plurality of acquisition tentacles as acquisition electrodes; the support member is a hollow cylinder, the acquisition tentacles are disposed along a circumference of a first port of the support member, and the first port is connected to the cap; the acquisition tentacles are in contact with a user's scalp to acquire the user's EEG signal; a near-red signal acquisition device which comprises a light guide column, a near infrared light source and a photodiode; the light guide column is a transparent hollow cylinder with a diameter smaller than that of the support member; the light guide column is disposed within an inner periphery of the support member, the near infrared light source and the photodiode are disposed at a second port of the light guide column, and the first port of the light guide column is fixed on the cap; after near infrared light emitted by the near infrared light source arrives at the user's cerebral cortex through the light guide column; the photodiode receives near infrared light not absorbed by oxyhemoglobin and deoxyhemoglobin of the user's cerebral cortex which is scattered and arrives at the photodiode through the light guide column, and converts the unabsorbed near infrared light into a current signal; a transimpedance amplifier connected to the photodiode and configured to convert the current signal into an analog voltage signal; a first analog-to-digital converter connected to the EEG signal acquisition device and configured to convert the EEG signal into a first digital signal; a second analog-to-digital converter connected to the transimpedance amplifier and configured to convert the analog voltage signal into a second digital signal; and a micro-control unit connected to the first analog-to-digital converter and the second analog-to-digital converter, and configured to receive the first digital signal output by the first analog-to-digital converter and the second digital signal output by the second analog-to-digital converter. a cap; an electroencephalogram signal acquisition device which comprises a support member and a plurality of acquisition tentacles as acquisition electrodes; the support member is a hollow cylinder, the acquisition tentacles are disposed along a circumference of a first port of the support member, and the first port is connected to the cap; the acquisition tentacles are in contact with a user's scalp to acquire the user's EEG signal; a near-red signal acquisition device which comprises a light guide column, a near infrared light source and a photodiode; the light guide column is a transparent hollow cylinder with a diameter smaller than that of the support member; the light guide column is disposed within an inner periphery of the support member, the near infrared light source and the photodiode are disposed at a second port of the light guide column, and the first port of the light guide column is fixed on the cap; after near infrared light emitted by the near infrared light source arrives at the user's cerebral cortex through the light guide column; the photodiode receives near infrared light not absorbed by oxyhemoglobin and deoxyhemoglobin of the user's cerebral cortex which is scattered and arrives at the photodiode through the light guide column, and converts the unabsorbed near infrared light into a current signal; a transimpedance amplifier connected to the photodiode and configured to convert the current signal into an analog voltage signal; a first analog-to-digital converter connected to the EEG signal acquisition device and configured to convert the EEG signal into a first digital signal; a second analog-to-digital converter connected to the transimpedance amplifier and configured to convert the analog voltage signal into a second digital signal; and a micro-control unit connected to the first analog-to-digital converter and the second analog-to-digital converter, and configured to receive the first digital signal output by the first analog-to-digital converter and the second digital signal output by the second analog-to-digital converter.