---
title: PROSUB Nuclear Submarine Program
type: technology
url: "https://www.envisioning.com/research/aegis/brazil__prosub-nuclear-submarine-program"
hub: aegis
summary: Brazil cut first steel for its nuclear-powered submarine in June 2025 — it will be only the 7th country with nuclear sub capability, using domestically enriched uranium
---

# PROSUB Nuclear Submarine Program

Brazil cut first steel for its nuclear-powered submarine in June 2025 — it will be only the 7th country with nuclear sub capability, using domestically enriched uranium
- Technology Readiness Level: 6/9
- Impact: 2/5
- Investment: 3/5
The PROSUB program has two phases: Phase I built four conventional Scorpène-class submarines with French technology transfer (three delivered by December 2025, fourth launched). Phase II began in June 2025 with the first steel cut for Brazil's nuclear-powered submarine at the Itaguaí Naval Complex.

Brazil will enrich its own uranium fuel using domestically developed centrifuge technology — a capability shared by only a handful of countries. The nuclear submarine is designed for patrol and deterrence in the South Atlantic, protecting pre-salt oil fields and asserting sovereignty over Brazil's exclusive economic zone.

The program is decades behind schedule and over budget (originally planned for 2021 delivery), but the technology transfer model — building submarines in Brazil with progressively more domestic content — has created a shipbuilding industrial base that didn't exist before.

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Source: Envisioning — Technology Research Institute (https://www.envisioning.com/research/aegis/brazil__prosub-nuclear-submarine-program)