An electronic component mounting machine comprising: a storage section configured to store viscous fluid; a head section configured to hold an electronic component having a bump, to immerse the bump of the electronic component in the viscous fluid and to mount the electronic component on a board (B1, B2); an irradiation section configured to irradiate light to the bump to which the viscous fluid has been transferred; an imaging section configured to capture an image of the bump irradiated with the light by the irradiation section; and a control device, wherein the control device is configured to execute a film thickness adjusting routine comprising: detection processing for detecting a transfer amount of the viscous fluid transferred to the bump based on image data captured by the imaging section; determination processing for determining whether the transfer amount is an appropriate amount between a predetermined lower threshold and a predetermined upper threshold, and transfer processing for transferring the viscous fluid to the bump in accordance with the transfer amount being less than the predetermined lower threshold, characterized in that in the transfer processing, the control device is configured to divide a difference amount between the transfer amount and the predetermined lower threshold into multiple stages, and wherein the control device is configured to perform repetitive processing of increasing the film thickness of the fluid film formed by the viscous fluid stored in the storage section by an amount corresponding to the divided difference amount, to transfer the viscous fluid to the bump and to perform the film thickness adjusting routine again. a storage section configured to store viscous fluid; a head section configured to hold an electronic component having a bump, to immerse the bump of the electronic component in the viscous fluid and to mount the electronic component on a board (B1, B2); an irradiation section configured to irradiate light to the bump to which the viscous fluid has been transferred; an imaging section configured to capture an image of the bump irradiated with the light by the irradiation section; and a control device, wherein the control device is configured to execute a film thickness adjusting routine comprising: detection processing for detecting a transfer amount of the viscous fluid transferred to the bump based on image data captured by the imaging section; determination processing for determining whether the transfer amount is an appropriate amount between a predetermined lower threshold and a predetermined upper threshold, and transfer processing for transferring the viscous fluid to the bump in accordance with the transfer amount being less than the predetermined lower threshold, characterized in that in the transfer processing, the control device is configured to divide a difference amount between the transfer amount and the predetermined lower threshold into multiple stages, and wherein the control device is configured to perform repetitive processing of increasing the film thickness of the fluid film formed by the viscous fluid stored in the storage section by an amount corresponding to the divided difference amount, to transfer the viscous fluid to the bump and to perform the film thickness adjusting routine again. detection processing for detecting a transfer amount of the viscous fluid transferred to the bump based on image data captured by the imaging section; determination processing for determining whether the transfer amount is an appropriate amount between a predetermined lower threshold and a predetermined upper threshold, and transfer processing for transferring the viscous fluid to the bump in accordance with the transfer amount being less than the predetermined lower threshold, characterized in that in the transfer processing, the control device is configured to divide a difference amount between the transfer amount and the predetermined lower threshold into multiple stages, and wherein the control device is configured to perform repetitive processing of increasing the film thickness of the fluid film formed by the viscous fluid stored in the storage section by an amount corresponding to the divided difference amount, to transfer the viscous fluid to the bump and to perform the film thickness adjusting routine again.