Alibaba adds 0.8B and 2B sizes to Qwen3.5, with 262K context and a vision encoder

Alibaba’s Qwen team released Qwen3.5-0.8B and Qwen3.5-2B on March 2, 2026, together with 4B and 9B versions, according to the Qwen release notes. Both are dense vision-language models with a 262,144-token context and Apache 2.0 weights. The model card states that the released files work with Hugging Face Transformers, vLLM, SGLang and KTransformers, and that in light of the parameter scale the intended uses are prototyping, task-specific fine-tuning and other research or development purposes.

The benchmark table in that model card puts Qwen3.5-2B at 55.3 on MMLU-Pro with reasoning switched off, where the same table gives 40.2 for last generation’s Qwen3-1.7B and 69.6 for the larger Qwen3-4B-2507, and Qwen3.5-0.8B at 29.7. With reasoning on, Alibaba reports 66.5 for the 2B and 42.3 for the 0.8B on the same test, and 51.6 against 11.9 on GPQA, a set of graduate-level science questions. The same table has Qwen3-1.7B ahead of both new sizes on IFEval, which checks whether a model obeys explicit formatting instructions, at 68.2 against 61.2 for the 2B and 52.1 for the 0.8B with reasoning off. Alibaba ran all of these figures itself.

Both sizes ship a vision encoder in the same checkpoint rather than as a separate release, and Alibaba’s vision table gives Qwen3.5-2B 64.2 on MMMU, a college-level image question set, above the 61.4 it lists for the previous Qwen3-VL-2B, with 49 for Qwen3.5-0.8B. The two models stack 24 layers in which three linear-attention blocks, whose memory cost does not grow with the sequence, alternate with one full-attention block. Input embedding and output layer are tied, so a single 248,320-entry matrix does both jobs, and Alibaba puts language coverage at 201 languages and dialects.

Alibaba published the weights on Hugging Face and ModelScope under Apache 2.0, and its MNN team put 4-bit exports of both sizes up the same day. The 0.8B build carries a 470 MB language weight file plus 63 MB for the vision encoder, and the 2B build 1.18 GB plus 196 MB, against 1.75 GB and 4.55 GB for the full-precision checkpoints. For other local runtimes the Qwen repository points readers to llama.cpp, which it says supports the series for text and vision, and to mlx-lm and mlx-vlm on Apple silicon, without Alibaba publishing GGUF or MLX builds of these sizes itself.