Mixed　platoon　with　a　human-driven　leading　vehicle　may　be　a　transition　mode　prior　to　the　widespread　adoption　of　fully　autonomous　platoon.　Enhancing　the　driving　safety　of　the　leading　vehicle　driver　is　crucial　for　improving　the　overall　operational　safety　of　the　mixed　platoon.　Predictive-Forward-Collision-Warning　(PFCW),　an　emerging　technology　in　transportation,　holds　promise　in　mitigating　collision　risks　for　drivers　by　presenting　traffic　information　beyond　their　immediate　visual　range.　However,　the　influence　characteristics　of　this　function　and　how　it　influences　the　evolution　of　collision　risk　in　leading　vehicle　driver　remain　unclear.　Therefore,　this　paper　attempts　to　analyse　the　quantitative　impact　of　PFCW　on　the　collision　risk　of　leading　vehicle　driver.　A　test　platform　for　connected　mixed　platoon　was　built　utilizing　driving　simulation　technology,　alongside　the　development　of　a　connected　Human-Machine　Interface　(HMI)　incorporating　PFCW　functionality.　To　evaluate　the　longitudinal　collision　risk　of　leading　vehicle　driver,　a　time-frequency　analysis　method　was　employed,　focusing　on　key　indicators:　deceleration　rate　to　avoid　collision　(DRAC),　time　to　collision　(TTC),　and　proportion　of　stopping　distance　(PSD).　The　time-domain　analysis　results　indicated　that　PFCW　can　significantly　mitigate　the　collision　risk　of　leading　vehicle.　Wavelet　transform　results　demonstrated　that　PFCW　can　ameliorate　drivers＇　abnormal　driving　behavior　and　mitigate　the　collision　risk　in　emergency　situation　of　impending　collision　moment.　Meanwhile,　PFCW　can　enhance　the　overall　operation　safety　of　the　mixed　platoon.　This　paper　leverages　driving　simulation　technology　and　multidimensional　indicators　to　analyze　the　quantitative　impact　of　PFCW　on　the　collision　risk　of　leading　vehicle　driver　during　rapid　deceleration　of　preceding　vehicles.　The　findings　can　guide　the　development　of　test　standards　for　connected　mixed　platoon,　the　promotion　and　application　of　PFCW,　and　the　advancement　of　Navigate　on　Autopilot　(NOA).　Additionally,　the　test　platform　and　framework　developed　in　this　study　can　accommodate　various　experimental　needs　for　connected　mixed　platoon　testing.