<p>Precise Point Positioning (PPP) technology has been widely applied in the field of time transfer, but most current research on PPP time transfer focuses on static environments, with less research being conducted in kinematic oceanic environments. To explore the performance of Multi-global Navigation Satellite System (GNSS) kinematic PPP time transfer in ocean environments, a set of measured ocean GNSS data was selected, and four experimental strategies were employed to compare the time and frequency transfer performance of single GPS and multi-GNSS kinematic PPP under different elevation cutoff angles, as well as to examine the effects of different system clock parameter solution strategies and additional Doppler observation constraint positions on kinematic PPP time transfer. The experimental results show that: (1) when the common clock strategy is used to eliminate the influence of the clock source, the precision of ocean multi-GNSS kinematic PPP time transfer is better than 0.5&#xa0;ns, the frequency stability at 1&#xa0;s and 40,000&#xa0;s averaging time is better than 5 × 10⁻¹¹ and 9 × 10⁻¹⁵; (2) the clock parameter strategy of estimating a common clock and using Random Walk (RW) model to constrain the Inter System Biases (ISBs) for other systems has better time transfer precision and long-term frequency stability than the strategy for estimating each GNSS clock; (3) the use of Doppler observation constraint positions can improve the medium-term frequency stability, and when data interruption occurs, the time transfer precision is improved by more than 20%.</p>