The invention relates to the technical field of oil and gas deep processing, and discloses a floating type device for producing methanol from natural gas and storing and offloading the methanol. The device can be applied to rivers, lakes and seas. The device comprises a ship type floating body, a start-up boiler device and methanol producing process devices. The start-up boiler device and the methanol producing process devices are arranged on a deck of the ship type floating body. The methanol producing process devices sequentially comprise a natural gas purification device, a natural gas conversion device, a methanol synthesis device and a methanol rectification device from upstream to downstream. The front end of the natural gas purification device is connected with a natural gas pipeline, an outlet of the start-up boiler device is connected with the natural gas conversion device, a seawater desalination device is arranged in the ship type floating body, an outlet of the seawater desalination device is connected with a desalted water device, and an outlet of the desalted water device is connected with the natural gas conversion device; a methanol intermediate product cabin and amethanol product cabin are further arranged in the ship type floating body, the output end of the methanol synthesis device is connected with the methanol intermediate product cabin, the methanol rectification device is connected between the methanol intermediate product cabin and the methanol product cabin. According to the device, the adopted natural gas is clean energy, dust emission is avoided, and the environment is protected.