Globally and in Timor-Leste, wasting and stunting remain major public health problems among 'under five years children, but the interrelationship between the two has been poorly investigated. A better understanding of this interrelationship is a prerequisite to improving wasting and stunting programming. In our study, we assessed the influence of age on the prevalence of wasting and stunting, the overlap between the two conditions, and the effect of wasting parameters on linear growth catch-up using the data of 401 children recruited at 0 to 54 months of age [median (IQR) of 17 (7-32) months] with repeated anthropometric assessments [median (IQR) follow-up time was 25 (16-39) months]. At recruitment, prevalences of stunting, wasting and concurrence of the two conditions were 54.6%, 9.5% and 4.6%, respectively. These prevalences were already high and above the thresholds for public health importance among children below months of age and remained high throughouttheir childhood. Over the follow-up period, the change (95%CI) in Height-for-Age Z-score (HAZ) was -0.01 (-0.13; 0.11) (p = 0.850), and that of the Height-for-Age Difference (HAD) was -3.74 (-4.28; -3.21) cm (p<0.001). Stunting reversal was observed in 25.6% of those stunted at recruitment, while a positive change in HAD was observed in only 19.6% of assessed children. Path analysis by structural equation modelling showed no significant direct effect of WHZ at recruitment on the likelihood of positive change in HAD, with its influence being fully mediated by its change over the follow-up period. This change had an inverse relationship with the occurrence of a positive change in HAD. On the contrary, Mid-Upper Arm Circumference at recruitment had a significant positive direct effect on the likelihood of a positive HAD change. These results show that interventions to combat wasting and stunting need to be integrated.