The invention provides a video coding method and a video coding device. The method for training a video coder provided by the embodiment of the invention comprises the following steps of setting the coder to be a secondary coding mode; determining a plurality of target code rates; providing a plurality of training video sources, and executing the following operations on each training video source: using one of the plurality of target code rates as a target code rate, and acquiring a quantization parameter value of the training video source which passes through the coder for the first time; changing the target code rate, and repeating the above steps until the plurality of target code rates are traversed; and determining a relation curve of the target code rates and the quantization parameters of the training video sources. The method also comprises the step of acquiring a fitting curve based on one or more curves in respective relation curves of the target code rates and the quantization parameters of the plurality of training video sources, wherein the fitting curve is to be applied to subsequent video coding of the coder.